Knowledge (XXG)

Robust statistics

Source 📝

8436: 516:, and remove them, usually checking the source of the data to see whether the outliers were erroneously recorded. Indeed, in the speed-of-light example above, it is easy to see and remove the two outliers prior to proceeding with any further analysis. However, in modern times, data sets often consist of large numbers of variables being measured on large numbers of experimental units. Therefore, manual screening for outliers is often impractical. 193: 8422: 996: 8460: 312:. If the dataset is, e.g., the values {2,3,5,6,9}, then if we add another datapoint with value -1000 or +1000 to the data, the resulting mean will be very different from the mean of the original data. Similarly, if we replace one of the values with a datapoint of value -1000 or +1000 then the resulting mean will be very different from the mean of the original data. 8448: 323:. Taking the same dataset {2,3,5,6,9}, if we add another datapoint with value -1000 or +1000 then the median will change slightly, but it will still be similar to the median of the original data. If we replace one of the values with a data point of value -1000 or +1000 then the resulting median will still be similar to the median of the original data. 1057: 941: 257:- robustness to breaking of the assumptions about the underlying distribution of the data. Classical statistical procedures are typically sensitive to "longtailedness" (e.g., when the distribution of the data has longer tails than the assumed normal distribution). This implies that they will be strongly affected by the presence of 2090: 5102:
can sometimes be accommodated in the data through the use of trimmed means, other scale estimators apart from standard deviation (e.g., MAD) and Winsorization. In calculations of a trimmed mean, a fixed percentage of data is dropped from each end of an ordered data, thus eliminating the outliers. The
4248:
Since M-estimators are normal only asymptotically, for small sample sizes it might be appropriate to use an alternative approach to inference, such as the bootstrap. However, M-estimates are not necessarily unique (i.e., there might be more than one solution that satisfies the equations). Also, it is
444:
The distribution of the mean is clearly much wider than that of the 10% trimmed mean (the plots are on the same scale). Also whereas the distribution of the trimmed mean appears to be close to normal, the distribution of the raw mean is quite skewed to the left. So, in this sample of 66 observations,
920:
If we replace the lowest observation, −44, by −1000, the mean becomes 11.73, whereas the 10% trimmed mean is still 27.43. In many areas of applied statistics, it is common for data to be log-transformed to make them near symmetrical. Very small values become large negative when log-transformed, and
1064:
The empirical influence function is a measure of the dependence of the estimator on the value of any one of the points in the sample. It is a model-free measure in the sense that it simply relies on calculating the estimator again with a different sample. On the right is Tukey's biweight function,
877:
The higher the breakdown point of an estimator, the more robust it is. Intuitively, we can understand that a breakdown point cannot exceed 50% because if more than half of the observations are contaminated, it is not possible to distinguish between the underlying distribution and the contaminating
579:
is the proportion of incorrect observations (e.g. arbitrarily large observations) an estimator can handle before giving an incorrect (e.g., arbitrarily large) result. Usually, the asymptotic (infinite sample) limit is quoted as the breakdown point, although the finite-sample breakdown point may be
397:
Although the bulk of the data looks to be more or less normally distributed, there are two obvious outliers. These outliers have a large effect on the mean, dragging it towards them, and away from the center of the bulk of the data. Thus, if the mean is intended as a measure of the location of the
2127:
Instead of relying solely on the data, we could use the distribution of the random variables. The approach is quite different from that of the previous paragraph. What we are now trying to do is to see what happens to an estimator when we change the distribution of the data slightly: it assumes a
477:
The outliers in the speed-of-light data have more than just an adverse effect on the mean; the usual estimate of scale is the standard deviation, and this quantity is even more badly affected by outliers because the squares of the deviations from the mean go into the calculation, so the outliers'
5110:
However, using these types of models to predict missing values or outliers in a long time series is difficult and often unreliable, particularly if the number of values to be in-filled is relatively high in comparison with total record length. The accuracy of the estimate depends on how good and
4252:
Of course, as we saw with the speed-of-light example, the mean is only normally distributed asymptotically and when outliers are present the approximation can be very poor even for quite large samples. However, classical statistical tests, including those based on the mean, are typically bounded
519:
Outliers can often interact in such a way that they mask each other. As a simple example, consider a small univariate data set containing one modest and one large outlier. The estimated standard deviation will be grossly inflated by the large outlier. The result is that the modest outlier looks
503:
The distribution of standard deviation is erratic and wide, a result of the outliers. The MAD is better behaved, and Qn is a little bit more efficient than MAD. This simple example demonstrates that when outliers are present, the standard deviation cannot be recommended as an estimate of scale.
5138:
non-robust initial fit can suffer from the effect of masking, that is, a group of outliers can mask each other and escape detection. Second, if a high breakdown initial fit is used for outlier detection, the follow-up analysis might inherit some of the inefficiencies of the initial estimator.
908:
In the speed-of-light example, removing the two lowest observations causes the mean to change from 26.2 to 27.75, a change of 1.55. The estimate of scale produced by the Qn method is 6.3. We can divide this by the square root of the sample size to get a robust standard error, and we find this
5137:
One common approach to handle outliers in data analysis is to perform outlier detection first, followed by an efficient estimation method (e.g., the least squares). While this approach is often useful, one must keep in mind two challenges. First, an outlier detection method that relies on a
5067:
is such a function that is also a statistic, meaning that it is computed in terms of the data alone. Such functions are robust to parameters in the sense that they are independent of the values of the parameters, but not robust to the model in the sense that they assume an underlying model
3527: 284:
for distributional robustness, and reserve 'robustness' for non-distributional robustness, e.g., robustness to violation of assumptions about the probability model or estimator, but this is a minority usage. Plain 'robustness' to mean 'distributional robustness' is common.
120:, where one mixes in a small amount (1–5% is often sufficient) of contamination. For instance, one may use a mixture of 95% a normal distribution, and 5% a normal distribution with the same mean but significantly higher standard deviation (representing outliers). 4560: 4633:
M-estimators do not necessarily relate to a density function and so are not fully parametric. Fully parametric approaches to robust modeling and inference, both Bayesian and likelihood approaches, usually deal with heavy-tailed distributions such as Student's
401:
Also, the distribution of the mean is known to be asymptotically normal due to the central limit theorem. However, outliers can make the distribution of the mean non-normal, even for fairly large data sets. Besides this non-normality, the mean is also
330:, the median has a breakdown point of 50%, meaning that half the points must be outliers before the median can be moved outside the range of the non-outliers, while the mean has a breakdown point of 0, as a single large observation can throw it off. 882:. Therefore, the maximum breakdown point is 0.5 and there are estimators which achieve such a breakdown point. For example, the median has a breakdown point of 0.5. The X% trimmed mean has a breakdown point of X%, for the chosen level of X. 5119:(KSOM) offers a simple and robust multivariate model for data analysis, thus providing good possibilities to estimate missing values, taking into account their relationship or correlation with other pertinent variables in the data record. 1589: 2963: 1831: 455:
Robust statistical methods, of which the trimmed mean is a simple example, seek to outperform classical statistical methods in the presence of outliers, or, more generally, when underlying parametric assumptions are not quite correct.
4960: 5115:(rather than the univariate approach of most traditional methods of estimating missing values and outliers). In such cases, a multivariate model will be more representative than a univariate one for predicting missing values. The 89:. In statistics, classical estimation methods rely heavily on assumptions that are often not met in practice. In particular, it is often assumed that the data errors are normally distributed, at least approximately, or that the 2624: 3008:
of the contamination (the asymptotic bias caused by contamination in the observations). For a robust estimator, we want a bounded influence function, that is, one which does not go to infinity as x becomes arbitrarily large.
4597:
function is not critical to gaining a good robust estimate, and many choices will give similar results that offer great improvements, in terms of efficiency and bias, over classical estimates in the presence of outliers.
1726: 546:
Although this article deals with general principles for univariate statistical methods, robust methods also exist for regression problems, generalized linear models, and parameter estimation of various distributions.
3338: 1355: 771: 3228: 916:
The 10% trimmed mean for the speed-of-light data is 27.43. Removing the two lowest observations and recomputing gives 27.67. The trimmed mean is less affected by the outliers and has a higher breakdown point.
2384: 5049: 264:
By contrast, more robust estimators that are not so sensitive to distributional distortions such as longtailedness are also resistant to the presence of outliers. Thus, in the context of robust statistics,
2099:-th value in the sample by an arbitrary value and looking at the output of the estimator. Alternatively, the EIF is defined as the effect, scaled by n+1 instead of n, on the estimator of adding the point 3351: 1400: 1457: 5094:. If there are relatively few missing points, there are some models which can be used to estimate values to complete the series, such as replacing missing values with the mean or median of the data. 530:
Robust methods provide automatic ways of detecting, downweighting (or removing), and flagging outliers, largely removing the need for manual screening. Care must be taken; initial data showing the
527:
problems, diagnostic plots are used to identify outliers. However, it is common that once a few outliers have been removed, others become visible. The problem is even worse in higher dimensions.
134:
by replacing estimators that are optimal under the assumption of a normal distribution with estimators that are optimal for, or at least derived for, other distributions; for example, using the
4726: 4200:
increases at an accelerating rate, whilst for absolute errors, it increases at a constant rate. When Winsorizing is used, a mixture of these two effects is introduced: for small values of x,
4449: 261:
in the data, and the estimates they produce may be heavily distorted if there are extreme outliers in the data, compared to what they would be if the outliers were not included in the data.
4412: 4056: 4242:
M-estimators do not necessarily relate to a probability density function. Therefore, off-the-shelf approaches to inference that arise from likelihood theory can not, in general, be used.
2323: 3995: 3771: 1293: 1111: 4245:
It can be shown that M-estimators are asymptotically normally distributed so that as long as their standard errors can be computed, an approximate approach to inference is available.
3912: 3828: 1149: 459:
Whilst the trimmed mean performs well relative to the mean in this example, better robust estimates are available. In fact, the mean, median and trimmed mean are all special cases of
4220:
increases at the squared rate, but once the chosen threshold is reached (1.5 in this example), the rate of increase becomes constant. This Winsorised estimator is also known as the
2275: 5111:
representative the model is and how long the period of missing values extends. When dynamic evolution is assumed in a series, the missing data point problem becomes an exercise in
3705: 1499: 1210: 1645: 650: 2734: 1770: 2203: 872: 696: 4249:
possible that any particular bootstrap sample can contain more outliers than the estimator's breakdown point. Therefore, some care is needed when designing bootstrap schemes.
4256:
These considerations do not "invalidate" M-estimation in any way. They merely make clear that some care is needed in their use, as is true of any other method of estimation.
1068:
In mathematical terms, an influence function is defined as a vector in the space of the estimator, which is in turn defined for a sample which is a subset of the population:
826: 959: 2820: 3639:. However, M-estimators now appear to dominate the field as a result of their generality, their potential for high breakdown points and comparatively high efficiency. See 3106: 3076: 2761: 1244: 4441: 3046: 234:
is resistant to errors in the results, produced by deviations from assumptions (e.g., of normality). This means that if the assumptions are only approximately met, the
4198: 2177: 1803: 1171: 4989: 4755: 2085:{\displaystyle EIF_{i}:x\in {\mathcal {X}}\mapsto n\cdot (T_{n}(x_{1},\dots ,x_{i-1},x,x_{i+1},\dots ,x_{n})-T_{n}(x_{1},\dots ,x_{i-1},x_{i},x_{i+1},\dots ,x_{n}))} 1504: 5861: 5750: 5595: 4843: 4619: 4595: 4322: 4302: 4227:
Tukey's biweight (also known as bisquare) function behaves in a similar way to the squared error function at first, but for larger errors, the function tapers off.
4218: 4159: 4139: 4119: 4099: 4076: 3932: 3848: 2828: 2787: 4863: 4823: 4803: 4783: 4663: 4304:, which means we can derive the properties of such an estimator (such as its rejection point, gross-error sensitivity or local-shift sensitivity) when we know its 7557: 3646:
M-estimators are not inherently robust. However, they can be designed to achieve favourable properties, including robustness. M-estimator are a generalization of
2701: 799: 8062: 4282: 3614: 3594: 3574: 3554: 3006: 2986: 2675: 2655: 2487: 2467: 2447: 2427: 2404: 2243: 2223: 2157: 2117: 1823: 598: 4886: 5063:
is a function of data, whose underlying population distribution is a member of a parametric family, that is not dependent on the values of the parameters. An
8212: 7836: 5977:
Rustum, Rabee; Adeloye, Adebayo J. (September 2007), "Replacing outliers and missing values from activated sludge data using Kohonen self-organizing map",
85:
Robust statistics seek to provide methods that emulate popular statistical methods, but are not unduly affected by outliers or other small departures from
2498: 6477: 7610: 4253:
above by the nominal size of the test. The same is not true of M-estimators and the type I error rate can be substantially above the nominal level.
8049: 1650: 5902: 520:
relatively normal. As soon as the large outlier is removed, the estimated standard deviation shrinks, and the modest outlier now looks unusual.
5072:, frequently constructed in terms of these to not be sensitive to assumptions about parameters, are still very sensitive to model assumptions. 3241: 6101: 5809: 5724: 5490: 5269: 5234: 4785:
can be estimated from the data in the same way as any other parameter. In practice, it is common for there to be multiple local maxima when
1300: 6472: 6172: 5511:, Wiley Series in Probability and Mathematical Statistics: Probability and Mathematical Statistics, New York: John Wiley & Sons, Inc., 701: 498: 5971: 3120: 1065:
which, as we will later see, is an example of what a "good" (in a sense defined later on) empirical influence function should look like.
7076: 6224: 8464: 2332: 5907:, Wiley Series in Probability and Mathematical Statistics: Applied Probability and Statistics, New York: John Wiley & Sons, Inc., 4997: 1017: 288:
When considering how robust an estimator is to the presence of outliers, it is useful to test what happens when an extreme outlier is
4232: 4166: 3522:{\displaystyle \lambda ^{*}(T;F):=\sup _{(x,y)\in {\mathcal {X}}^{2} \atop x\neq y}\left\|{\frac {IF(y;T;F)-IF(x;T;F)}{y-x}}\right\|} 450: 7859: 7751: 5920: 5698: 5671: 5641: 5516: 1043: 977: 489:
of scale. The plots are based on 10,000 bootstrap samples for each estimator, with some Gaussian noise added to the resampled data (
8037: 7911: 4870: 1362: 8095: 7756: 7501: 6872: 6462: 6128: 1406: 7086: 5315: 371:
are a general class of robust statistics, and are now the preferred solution, though they can be quite involved to calculate.
8146: 7358: 7165: 7054: 7012: 1021: 429:(d). The trimmed mean is a simple, robust estimator of location that deletes a certain percentage of observations (10% here) 6251: 8389: 7348: 93:
can be relied on to produce normally distributed estimates. Unfortunately, when there are outliers in the data, classical
7398: 7940: 7889: 7874: 7864: 7733: 7605: 7572: 7353: 7183: 6145: 4555:{\displaystyle M=-\int _{\mathcal {X}}\left({\frac {\partial \psi (x,\theta )}{\partial \theta }}\right)_{T(F)}\,dF(x).} 3647: 8009: 7310: 5068:(parametric family), and in fact, such functions are often very sensitive to violations of the model assumptions. Thus 4671: 8284: 8085: 7064: 6733: 6197: 5347: 5147: 8169: 8136: 1006: 135: 5827:
Rosen, C.; Lennox, J.A. (October 2001), "Multivariate and multiscale monitoring of wastewater treatment operation",
8486: 8141: 7884: 7643: 7549: 7529: 7437: 7148: 6966: 6449: 6321: 4330: 490: 438: 7315: 7081: 6939: 4000: 1025: 1010: 7901: 7669: 7390: 7244: 7173: 7093: 6951: 6932: 6640: 6361: 6003: 2280: 482: 334: 8014: 1256: 1074: 8384: 8151: 7699: 7664: 7628: 7413: 6855: 6764: 6723: 6635: 6326: 6165: 6088:, Statistical Modeling and Decision Science (3rd ed.), Amsterdam: Elsevier/Academic Press, pp. 1–22, 5157: 5107:
involves accommodating an outlier by replacing it with the next highest or next smallest value as appropriate.
5095: 3937: 3710: 486: 472: 434: 7421: 7405: 1118: 3860: 3776: 8293: 7906: 7846: 7783: 7143: 7005: 6995: 6845: 6759: 6040:
Ting, Jo-anne; Theodorou, Evangelos; Schaal, Stefan (2007), "A Kalman filter for robust outlier detection",
5112: 5091: 5081: 2248: 403: 247: 239: 112:
The practical effect of problems seen in the influence function can be studied empirically by examining the
8054: 7991: 4880:
For the speed-of-light data, allowing the kurtosis parameter to vary and maximizing the likelihood, we get
4621:
functions are to be preferred, and Tukey's biweight (also known as bisquare) function is a popular choice.
1469: 1180: 8331: 8261: 7746: 7633: 6630: 6527: 6434: 6313: 6212: 5990: 5557:; Portnoy, Stephen (1992), "Reweighted LS estimators converge at the same rate as the initial estimator", 5131: 3653: 1598: 603: 342: 172: 166: 86: 50: 8452: 7330: 5534:
Harvey, A. C.; Fernandes, C. (October 1989), "Time Series Models for Count or Qualitative Observations",
4761:-distribution is equivalent to the Cauchy distribution. The degrees of freedom is sometimes known as the 2709: 1731: 8356: 8298: 8241: 8067: 7960: 7869: 7595: 7479: 7338: 7220: 7212: 7027: 6923: 6901: 6860: 6825: 6792: 6738: 6713: 6668: 6607: 6567: 6369: 6192: 2182: 2132:
and measures sensitivity to change in this distribution. By contrast, the empirical influence assumes a
831: 773:
to estimate the mean. Such an estimator has a breakdown point of 0 (or finite-sample breakdown point of
655: 296:
one of the existing data points, and then to consider the effect of multiple additions or replacements.
124: 113: 90: 62: 61:. Another motivation is to provide methods with good performance when there are small departures from a 8435: 7325: 37:
that maintain their properties even if the underlying distributional assumptions are incorrect. Robust
6133: 5711:, Wiley Series in Probability and Statistics (2nd ed.), Chichester: John Wiley & Sons, Ltd., 5177: 3631:(The mathematical context of this paragraph is given in the section on empirical influence functions.) 8279: 7854: 7803: 7779: 7741: 7659: 7638: 7590: 7469: 7447: 7416: 7202: 7153: 7071: 7044: 7000: 6956: 6718: 6494: 6374: 5559: 804: 8426: 8351: 8274: 7955: 7719: 7712: 7674: 7582: 7562: 7534: 7267: 7133: 7128: 7118: 7110: 6928: 6889: 6779: 6769: 6678: 6457: 6413: 6331: 6256: 6158: 5116: 5064: 4221: 2792: 524: 338: 66: 8001: 3084: 273:
are effectively synonymous. For one perspective on research in robust statistics up to 2000, see
8440: 8251: 8105: 7950: 7826: 7723: 7707: 7684: 7461: 7195: 7178: 7138: 7049: 6944: 6906: 6877: 6837: 6797: 6743: 6660: 6346: 6341: 6028: 5962: 5938: 5898: 5878: 5856: 5767: 5612: 5543: 5504: 5251: 5216: 3533: 3054: 2739: 2634: 2326: 1217: 350: 346: 154: 70: 54: 42: 3635:
Historically, several approaches to robust estimation were proposed, including R-estimators and
930: 4420: 3024: 1584:{\displaystyle X_{1},\dots ,X_{n}:(\Omega ,{\mathcal {A}})\rightarrow ({\mathcal {X}},\Sigma )} 8346: 8316: 8308: 8128: 8119: 8044: 7975: 7831: 7816: 7791: 7679: 7620: 7486: 7474: 7100: 6961: 6884: 6728: 6650: 6429: 6303: 6097: 6050: 5916: 5844: 5805: 5799: 5720: 5694: 5667: 5637: 5512: 5486: 5265: 5230: 5197: 5152: 4174: 2958:{\displaystyle IF(x;T;F):=\lim _{t\rightarrow 0^{+}}{\frac {T(t\Delta _{x}+(1-t)F)-T(F)}{t}}.} 391: 356: 243: 131:
by designing estimators so that a pre-selected behaviour of the influence function is achieved
5707:
Maronna, Ricardo A.; Martin, R. Douglas; Yohai, Victor J.; SalibiĂĄn-Barrera, MatĂ­as (2019) ,
2162: 1775: 1156: 493:). Panel (a) shows the distribution of the standard deviation, (b) of the MAD and (c) of Qn. 8371: 8326: 8090: 8077: 7970: 7945: 7879: 7811: 7689: 7297: 7190: 7123: 7036: 6983: 6802: 6673: 6467: 6266: 6233: 6089: 6062: 6012: 5986: 5954: 5908: 5870: 5836: 5787: 5759: 5712: 5604: 5568: 5257: 5222: 5189: 5060: 4968: 4734: 890:
contain more details. The level and the power breakdown points of tests are investigated in
523:
This problem of masking gets worse as the complexity of the data increases. For example, in
320: 309: 6111: 6076: 6024: 5930: 5890: 5819: 5779: 5681: 5651: 5624: 5582: 5526: 4828: 4604: 4580: 4307: 4287: 4203: 4144: 4124: 4104: 4084: 4061: 3917: 3833: 2766: 425:
Panels (c) and (d) of the plot show the bootstrap distribution of the mean (c) and the 10%
8288: 8032: 7894: 7821: 7496: 7370: 7343: 7320: 7289: 6916: 6911: 6865: 6595: 6246: 6125: 6107: 6072: 6020: 5998: 5926: 5886: 5815: 5775: 5677: 5647: 5620: 5578: 5522: 4848: 4808: 4788: 4768: 4648: 2631: 1174: 305: 160: 142: 46: 4955:{\displaystyle {\hat {\mu }}=27.40,\quad {\hat {\sigma }}=3.81,\quad {\hat {\nu }}=2.13.} 2680: 776: 8237: 8232: 6695: 6625: 6271: 6093: 5791: 5659: 5636:, Kendall's Library of Statistics, vol. 5, New York: John Wiley & Sons, Inc., 5069: 4267: 3599: 3579: 3559: 3539: 2991: 2971: 2660: 2640: 2472: 2452: 2432: 2412: 2389: 2228: 2208: 2142: 2102: 1808: 583: 383: 5840: 192: 8480: 8394: 8361: 8224: 8185: 7996: 7965: 7429: 7383: 6988: 6690: 6517: 6281: 6276: 5123: 3850:
is some function. MLE are therefore a special case of M-estimators (hence the name: "
921:
zeroes become negatively infinite. Therefore, this example is of practical interest.
387: 379: 250:, meaning having a bias tending towards 0 as the sample size tends towards infinity. 176: 117: 6547: 6032: 5966: 5593:; Simpson, Douglas G.; Portnoy, Stephen L. (1990), "Breakdown robustness of tests", 2619:{\displaystyle dT_{G-F}(F)=\lim _{t\rightarrow 0^{+}}{\frac {T(tG+(1-t)F)-T(F)}{t}}} 433:
of the data, then computes the mean in the usual way. The analysis was performed in
419: 8336: 8269: 8246: 8161: 7491: 6787: 6685: 6620: 6562: 6484: 6439: 5795: 5736:
Statistical procedures for analysis of environmental monitoring data and assessment
5500: 5087: 3017:
Properties of an influence function that bestow it with desirable performance are:
460: 426: 6139: 6053:(1947), "On the asymptotic distribution of differentiable statistical functions", 5351: 5323: 406:
in the presence of outliers and less variable measures of location are available.
8379: 8341: 8024: 7925: 7787: 7600: 7567: 7059: 6976: 6971: 6615: 6572: 6552: 6532: 6522: 6291: 5104: 3636: 3625: 995: 497: 481:
The plots below show the bootstrap distributions of the standard deviation, the
414:
The plot below shows a density plot of the speed-of-light data, together with a
364: 360: 17: 5193: 7225: 6705: 6405: 6336: 6286: 6261: 6181: 6067: 5942: 909:
quantity to be 0.78. Thus, the change in the mean resulting from removing two
535: 531: 38: 34: 5859:; Croux, Christophe (1993), "Alternatives to the median absolute deviation", 5573: 5201: 1721:{\displaystyle T_{n}:({\mathcal {X}}^{n},\Sigma ^{n})\rightarrow (\Gamma ,S)} 7378: 7230: 6850: 6645: 6557: 6542: 6537: 6502: 6016: 5745: 5590: 5554: 576: 230: 224: 94: 5848: 4765:. It is the parameter that controls how heavy the tails are. In principle, 5716: 5261: 5226: 4625:
recommend the biweight function with efficiency at the normal set to 85%.
4231: 4165: 449: 6894: 6512: 6389: 6384: 6379: 6351: 5099: 910: 513: 415: 398:
center of the data, it is, in a sense, biased when outliers are present.
41:
methods have been developed for many common problems, such as estimating
3333:{\displaystyle \gamma ^{*}(T;F):=\sup _{x\in {\mathcal {X}}}|IF(x;T;F)|} 382:
et al. in Bayesian Data Analysis (2004) consider a data set relating to
8399: 8100: 5912: 5882: 5771: 5616: 5547: 2968:
It describes the effect of an infinitesimal contamination at the point
2406:, the estimator sequence asymptotically measures the correct quantity. 258: 58: 1350:{\displaystyle ({\mathcal {X}},\Sigma )=(\mathbb {R} ,{\mathcal {B}})} 8321: 7302: 7276: 7256: 6507: 6298: 1592: 766:{\displaystyle {\overline {X_{n}}}:={\frac {X_{1}+\cdots +X_{n}}{n}}} 316: 74: 6134:
Nick Fieller's course notes on Statistical Modelling and Computation
5947:
Wiley Interdisciplinary Reviews: Data Mining and Knowledge Discovery
5874: 5763: 5608: 4869: 3773:. In 1964, Huber proposed to generalize this to the minimization of 1056: 445:
only 2 outliers cause the central limit theorem to be inapplicable.
394:
page, and the book's website contains more information on the data.
5958: 3223:{\displaystyle \rho ^{*}:=\inf _{r>0}\{r:IF(x;T;F)=0,|x|>r\}} 5336: 5256:. Wiley Series in Probability and Statistics (1 ed.). Wiley. 5221:. Wiley Series in Probability and Statistics (1 ed.). Wiley. 4622: 1055: 887: 6042:
International Conference on Intelligent Robots and Systems – IROS
3536:, represents the effect of shifting an observation slightly from 2379:{\displaystyle \forall \theta \in \Theta ,T(F_{\theta })=\theta } 292:
to the dataset, and to test what happens when an extreme outlier
6241: 5044:{\displaystyle {\hat {\mu }}=27.49,\quad {\hat {\sigma }}=4.51.} 555:
The basic tools used to describe and measure robustness are the
8210: 7777: 7524: 6823: 6593: 6210: 6154: 2159:
be a convex subset of the set of all finite signed measures on
149:
Robust estimates have been studied for the following problems:
6142:
contains course notes on robust statistics and some data sets.
5691:
Hidden Markov and Other Models for Discrete-Valued Time Series
4264:
It can be shown that the influence function of an M-estimator
989: 934: 367:
are a general class of simple statistics, often robust, while
187: 6150: 105: 5425: 5423: 4468: 3411: 3286: 2721: 1862: 1673: 1567: 1551: 1441: 1339: 1309: 1271: 1127: 1089: 512:
Traditionally, statisticians would manually screen data for
65:. For example, robust methods work well for mixtures of two 1395:{\displaystyle \Theta =\mathbb {R} \times \mathbb {R} ^{+}} 897:
Statistics with high breakdown points are sometimes called
5098:
can also be used to estimate missing values. In addition,
2988:
on the estimate we are seeking, standardized by the mass
2469:
exactly but another, slightly different, "going towards"
1452:{\displaystyle (\Gamma ,S)=(\mathbb {R} ,{\mathcal {B}})} 441:
samples were used for each of the raw and trimmed means.
6086:
Introduction to robust estimation and hypothesis testing
4825:
at a value around 4 or 6. The figure below displays the
1463:
The empirical influence function is defined as follows.
97:
often have very poor performance, when judged using the
5685:. Republished in paperback, 2004. 2nd ed., Wiley, 2009. 5178:"On some connections between statistics and cryptology" 955: 204: 175:
form, for which the standard method is equivalent to a
4003: 3940: 3863: 3779: 3713: 3656: 2449:. What happens when the data doesn't follow the model 422:(panel (b)). The outliers are visible in these plots. 141:
with low degrees of freedom (high kurtosis) or with a
5794:; Vetterling, William T.; Flannery, Brian P. (2007), 5250:
Huber, Peter J.; Ronchetti, Elvezio M. (2009-01-29).
5215:
Huber, Peter J.; Ronchetti, Elvezio M. (2009-01-29).
5000: 4971: 4889: 4851: 4831: 4811: 4791: 4771: 4737: 4674: 4651: 4607: 4583: 4452: 4423: 4333: 4310: 4290: 4270: 4206: 4177: 4147: 4127: 4107: 4087: 4064: 3920: 3836: 3602: 3582: 3562: 3542: 3354: 3244: 3123: 3087: 3057: 3027: 2994: 2974: 2831: 2795: 2769: 2742: 2712: 2683: 2663: 2643: 2501: 2475: 2455: 2435: 2415: 2392: 2335: 2283: 2251: 2231: 2211: 2185: 2165: 2145: 2105: 1834: 1811: 1778: 1734: 1653: 1601: 1507: 1472: 1409: 1365: 1303: 1259: 1220: 1183: 1159: 1121: 1077: 834: 807: 779: 704: 658: 606: 586: 8063:
Autoregressive conditional heteroskedasticity (ARCH)
4121:
have been proposed. The two figures below show four
363:
are general methods to make statistics more robust.
8370: 8307: 8260: 8223: 8178: 8160: 8127: 8118: 8076: 8023: 7984: 7933: 7924: 7845: 7802: 7732: 7698: 7652: 7619: 7581: 7548: 7460: 7369: 7288: 7243: 7211: 7164: 7109: 7035: 7026: 6836: 6778: 6752: 6704: 6659: 6606: 6493: 6448: 6422: 6404: 6360: 6312: 6232: 6223: 5945:(2011), "Robust statistics for outlier detection", 5127: 2277:be the asymptotic value of some estimator sequence 2136:and measures sensitivity to change in the samples. 950:
may be too technical for most readers to understand
390:. The data sets for that book can be found via the 5801:Numerical Recipes: The Art of Scientific Computing 5748:(2000), "A robust journey in the new millennium", 5103:mean is then calculated using the remaining data. 5043: 4983: 4954: 4857: 4837: 4817: 4797: 4777: 4749: 4720: 4657: 4613: 4589: 4554: 4435: 4406: 4316: 4296: 4276: 4212: 4192: 4153: 4133: 4113: 4093: 4070: 4050: 3989: 3926: 3906: 3842: 3822: 3765: 3699: 3608: 3588: 3568: 3548: 3521: 3332: 3222: 3100: 3070: 3040: 3000: 2980: 2957: 2814: 2781: 2755: 2728: 2695: 2669: 2649: 2618: 2481: 2461: 2441: 2421: 2398: 2378: 2317: 2269: 2237: 2217: 2197: 2171: 2151: 2111: 2084: 1817: 1797: 1764: 1720: 1639: 1583: 1493: 1451: 1394: 1349: 1287: 1238: 1204: 1165: 1143: 1105: 913:is approximately twice the robust standard error. 866: 820: 793: 765: 690: 644: 592: 538:were rejected as outliers by non-human screening. 171:estimation of model-states in models expressed in 5398: 4805:is allowed to vary. As such, it is common to fix 4721:{\displaystyle \psi (x)={\frac {x}{x^{2}+\nu }}.} 2763:is the probability measure which gives mass 1 to 5485:, Boca Raton, FL: Chapman & Hall/CRC Press, 4577:In many practical situations, the choice of the 3384: 3274: 3138: 2863: 2534: 891: 7611:Multivariate adaptive regression splines (MARS) 5862:Journal of the American Statistical Association 5751:Journal of the American Statistical Association 5596:Journal of the American Statistical Association 5402: 6001:(2010), "The changing history of robustness", 5709:Robust statistics: Theory and methods (with R) 5453: 5301: 879: 73:; under this model, non-robust methods like a 6166: 5689:MacDonald, Iain L.; Zucchini, Walter (1997), 5632:Hettmansperger, T. P.; McKean, J. W. (1998), 5536:Journal of Business & Economic Statistics 5429: 5182:Journal of Statistical Planning and Inference 4407:{\displaystyle IF(x;T,F)=M^{-1}\psi (x,T(F))} 4051:{\textstyle \psi (x)={\frac {d\rho (x)}{dx}}} 2822:. The influence function is then defined by: 2095:What this means is that we are replacing the 8: 5804:(3rd ed.), Cambridge University Press, 5414: 3217: 3153: 2776: 2770: 1759: 1741: 5441: 5130:have recently shown that a modification of 2318:{\displaystyle (T_{n})_{n\in \mathbb {N} }} 1024:. Unsourced material may be challenged and 223:There are various definitions of a "robust 8220: 8207: 8124: 7930: 7799: 7774: 7545: 7521: 7249: 7032: 6833: 6820: 6603: 6590: 6229: 6220: 6207: 6173: 6159: 6151: 3990:{\textstyle \sum _{i=1}^{n}\psi (x_{i})=0} 3766:{\textstyle \sum _{i=1}^{n}-\log f(x_{i})} 2325:. We will suppose that this functional is 1288:{\displaystyle (\Omega ,{\mathcal {A}},P)} 1106:{\displaystyle (\Omega ,{\mathcal {A}},P)} 828:arbitrarily large just by changing any of 6066: 5734:McBean, Edward A.; Rovers, Frank (1998), 5666:, New York: John Wiley & Sons, Inc., 5572: 5465: 5362: 5024: 5023: 5002: 5001: 4999: 4970: 4935: 4934: 4913: 4912: 4891: 4890: 4888: 4850: 4830: 4810: 4790: 4770: 4736: 4700: 4690: 4673: 4665:degrees of freedom, it can be shown that 4650: 4606: 4582: 4533: 4518: 4479: 4467: 4466: 4451: 4422: 4368: 4332: 4309: 4289: 4269: 4205: 4176: 4146: 4126: 4106: 4086: 4063: 4019: 4002: 3972: 3956: 3945: 3939: 3919: 3895: 3879: 3868: 3862: 3835: 3811: 3795: 3784: 3778: 3754: 3729: 3718: 3712: 3688: 3672: 3661: 3655: 3650:(MLEs) which is determined by maximizing 3601: 3581: 3561: 3541: 3441: 3416: 3410: 3409: 3387: 3359: 3353: 3325: 3293: 3285: 3284: 3277: 3249: 3243: 3206: 3198: 3141: 3128: 3122: 3092: 3086: 3062: 3056: 3032: 3026: 2993: 2973: 2901: 2885: 2877: 2866: 2830: 2806: 2794: 2768: 2747: 2741: 2720: 2719: 2711: 2682: 2662: 2642: 2556: 2548: 2537: 2509: 2500: 2474: 2454: 2434: 2414: 2391: 2361: 2334: 2309: 2308: 2301: 2291: 2282: 2250: 2230: 2210: 2184: 2164: 2144: 2104: 2070: 2045: 2032: 2013: 1994: 1981: 1965: 1940: 1915: 1896: 1883: 1861: 1860: 1845: 1833: 1810: 1789: 1777: 1733: 1691: 1678: 1672: 1671: 1658: 1652: 1628: 1609: 1600: 1566: 1565: 1550: 1549: 1531: 1512: 1506: 1485: 1481: 1480: 1471: 1440: 1439: 1432: 1431: 1408: 1386: 1382: 1381: 1373: 1372: 1364: 1338: 1337: 1330: 1329: 1308: 1307: 1302: 1270: 1269: 1258: 1219: 1196: 1192: 1191: 1182: 1158: 1126: 1125: 1120: 1088: 1087: 1076: 1044:Learn how and when to remove this message 978:Learn how and when to remove this message 962:, without removing the technical details. 858: 839: 833: 808: 806: 783: 778: 751: 732: 725: 711: 705: 703: 682: 663: 657: 633: 614: 605: 585: 274: 5634:Robust nonparametric statistical methods 5126:are not robust to outliers. To this end 3907:{\textstyle \sum _{i=1}^{n}\rho (x_{i})} 3823:{\textstyle \sum _{i=1}^{n}\rho (x_{i})} 2123:Influence function and sensitivity curve 1144:{\displaystyle ({\mathcal {X}},\Sigma )} 463:. Details appear in the sections below. 6146:Online experiments using R and JSXGraph 5991:10.1061/(asce)0733-9372(2007)133:9(909) 5904:Robust Regression and Outlier Detection 5285: 5283: 5281: 5168: 575:Intuitively, the breakdown point of an 8137:Kaplan–Meier estimator (product limit) 6136:contain material on robust regression. 2270:{\displaystyle T:A\rightarrow \Gamma } 5386: 5374: 5289: 5076:Replacing outliers and missing values 3914:can often be done by differentiating 3854:aximum likelihood type" estimators). 3700:{\textstyle \prod _{i=1}^{n}f(x_{i})} 3640: 3532:This value, which looks a lot like a 1494:{\displaystyle n\in \mathbb {N} ^{*}} 1205:{\displaystyle p\in \mathbb {N} ^{*}} 960:make it understandable to non-experts 883: 7: 8447: 8147:Accelerated failure time (AFT) model 5979:Journal of Environmental Engineering 5542:(4), Taylor & Francis: 407–417, 5316:"When was the ozone hole discovered" 4991:and maximizing the likelihood gives 4845:-function for 4 different values of 4260:Influence function of an M-estimator 2179:. We want to estimate the parameter 1640:{\displaystyle (x_{1},\dots ,x_{n})} 1151:is a measurable space (state space), 1022:adding citations to reliable sources 645:{\displaystyle (X_{1},\dots ,X_{n})} 418:(panel (a)). Also shown is a normal 327: 253:Usually, the most important case is 99: 8459: 7742:Analysis of variance (ANOVA, anova) 5128:Ting, Theodorou & Schaal (2007) 2729:{\displaystyle x\in {\mathcal {X}}} 1772:. The empirical influence function 1765:{\displaystyle i\in \{1,\dots ,n\}} 652:and the corresponding realizations 7837:Cochran–Mantel–Haenszel statistics 6463:Pearson product-moment correlation 6094:10.1016/B978-0-12-386983-8.00001-9 4505: 4482: 4141:functions and their corresponding 3388: 2898: 2803: 2744: 2345: 2336: 2264: 2198:{\displaystyle \theta \in \Theta } 2192: 2166: 1706: 1688: 1647:is a sample from these variables. 1575: 1543: 1413: 1366: 1317: 1263: 1224: 1160: 1135: 1081: 867:{\displaystyle x_{1},\dots ,x_{n}} 691:{\displaystyle x_{1},\dots ,x_{n}} 25: 6055:Annals of Mathematical Statistics 5934:. Republished in paperback, 2003. 5796:"Section 15.7. Robust Estimation" 5530:. Republished in paperback, 2005. 5483:Robust methods for data reduction 5481:Farcomeni, A.; Greco, L. (2013), 368: 8458: 8446: 8434: 8421: 8420: 4868: 4230: 4164: 994: 939: 892:He, Simpson & Portnoy (1990) 580:more useful. For example, given 496: 448: 191: 57:that are not unduly affected by 8096:Least-squares spectral analysis 6129:robust statistics course notes. 5399:MacDonald & Zucchini (1997) 5022: 4933: 4911: 2386:. This means that at the model 821:{\displaystyle {\overline {x}}} 116:of proposed estimators under a 53:. One motivation is to produce 7077:Mean-unbiased minimum-variance 5029: 5007: 4940: 4918: 4896: 4684: 4678: 4546: 4540: 4528: 4522: 4500: 4488: 4401: 4398: 4392: 4380: 4358: 4340: 4187: 4181: 4034: 4028: 4013: 4007: 3978: 3965: 3901: 3888: 3817: 3804: 3760: 3747: 3694: 3681: 3576:, i.e., add an observation at 3515: 3498: 3480: 3468: 3450: 3438: 3402: 3390: 3377: 3365: 3326: 3322: 3304: 3294: 3267: 3255: 3207: 3199: 3186: 3168: 3081:Small local-shift sensitivity 3051:Small gross-error sensitivity 2943: 2937: 2928: 2922: 2910: 2891: 2870: 2856: 2838: 2607: 2601: 2592: 2586: 2574: 2562: 2541: 2527: 2521: 2367: 2354: 2298: 2284: 2261: 2079: 2076: 1987: 1971: 1889: 1876: 1867: 1715: 1703: 1700: 1697: 1667: 1634: 1602: 1578: 1562: 1559: 1556: 1540: 1446: 1428: 1422: 1410: 1344: 1326: 1320: 1304: 1282: 1260: 1233: 1221: 1138: 1122: 1100: 1078: 639: 607: 485:(MAD) and the Rousseeuw–Croux 1: 8390:Geographic information system 7606:Simultaneous equations models 5841:10.1016/s0043-1354(01)00069-0 5403:Harvey & Fernandes (1989) 5176:Sarkar, Palash (2014-05-01). 3707:or, equivalently, minimizing 3648:maximum likelihood estimators 2815:{\displaystyle G=\Delta _{x}} 600:independent random variables 508:Manual screening for outliers 280:Some experts prefer the term 238:will still have a reasonable 145:of two or more distributions. 7573:Coefficient of determination 7184:Uniformly most powerful test 5507:; Stahel, Werner A. (1986), 5454:Rousseeuw & Leroy (1987) 5302:Rousseeuw & Croux (1993) 4876:Example: speed-of-light data 4629:Robust parametric approaches 3101:{\displaystyle \lambda ^{*}} 925:Empirical influence function 904:Example: speed-of-light data 880:Rousseeuw & Leroy (1987) 813: 717: 8142:Proportional hazards models 8086:Spectral density estimation 8068:Vector autoregression (VAR) 7502:Maximum posterior estimator 6734:Randomized controlled trial 5901:; Leroy, Annick M. (1987), 5655:. 2nd ed., CRC Press, 2011. 5430:Rustum & Adeloye (2007) 5148:Robust confidence intervals 5117:Kohonen self organising map 3071:{\displaystyle \gamma ^{*}} 2756:{\displaystyle \Delta _{x}} 1239:{\displaystyle (\Gamma ,S)} 308:is not a robust measure of 8503: 7902:Multivariate distributions 6322:Average absolute deviation 5415:McBean & Rovers (1998) 5194:10.1016/j.jspi.2013.05.008 5079: 4238:Properties of M-estimators 3623: 928: 470: 8416: 8219: 8206: 7890:Structural equation model 7798: 7773: 7544: 7520: 7252: 7226:Score/Lagrange multiplier 6832: 6819: 6641:Sample size determination 6602: 6589: 6219: 6206: 6188: 6004:The American Statistician 5503:; Ronchetti, Elvezio M.; 5442:Rosen & Lennox (2001) 4436:{\displaystyle p\times p} 3041:{\displaystyle \rho ^{*}} 1295:is any probability space, 1060:Tukey's biweight function 483:median absolute deviation 478:effects are exacerbated. 335:median absolute deviation 255:distributional robustness 127:can proceed in two ways: 8385:Environmental statistics 7907:Elliptical distributions 7700:Generalized linear model 7629:Simple linear regression 7399:Hodges–Lehmann estimator 6856:Probability distribution 6765:Stochastic approximation 6327:Coefficient of variation 5693:, Taylor & Francis, 5158:Unit-weighted regression 5134:can deal with outliers. 5096:Simple linear regression 4193:{\displaystyle \rho (x)} 3556:to a neighbouring point 2429:be some distribution in 473:Robust measures of scale 227:". Strictly speaking, a 8045:Cross-correlation (XCF) 7653:Non-standard predictors 7087:Lehmann–ScheffĂ© theorem 6760:Adaptive clinical trial 6068:10.1214/aoms/1177730385 6017:10.1198/tast.2010.10159 5466:He & Portnoy (1992) 5082:Imputation (statistics) 3344:Local-shift sensitivity 3234:Gross-error sensitivity 3021:Finite rejection point 2172:{\displaystyle \Sigma } 1798:{\displaystyle EIF_{i}} 1166:{\displaystyle \Theta } 1113:is a probability space, 542:Variety of applications 341:are robust measures of 319:is a robust measure of 275:Portnoy & He (2000) 267:distributionally robust 248:asymptotically unbiased 242:, and reasonably small 167:regression coefficients 63:parametric distribution 8441:Mathematics portal 8262:Engineering statistics 8170:Nelson–Aalen estimator 7747:Analysis of covariance 7634:Ordinary least squares 7558:Pearson product-moment 6962:Statistical functional 6873:Empirical distribution 6706:Controlled experiments 6435:Frequency distribution 6213:Descriptive statistics 5574:10.1214/aos/1176348910 5045: 4985: 4984:{\displaystyle \nu =4} 4956: 4859: 4839: 4819: 4799: 4779: 4751: 4750:{\displaystyle \nu =1} 4722: 4659: 4615: 4591: 4556: 4437: 4408: 4318: 4298: 4278: 4214: 4194: 4155: 4135: 4115: 4095: 4072: 4052: 3991: 3961: 3928: 3908: 3884: 3844: 3824: 3800: 3767: 3734: 3701: 3677: 3610: 3590: 3570: 3550: 3523: 3334: 3224: 3102: 3072: 3042: 3002: 2982: 2959: 2816: 2783: 2757: 2730: 2697: 2677:, in the direction of 2671: 2651: 2620: 2483: 2463: 2443: 2423: 2400: 2380: 2319: 2271: 2239: 2219: 2199: 2173: 2153: 2113: 2086: 1819: 1799: 1766: 1722: 1641: 1585: 1495: 1453: 1396: 1351: 1289: 1246:is a measurable space, 1240: 1206: 1167: 1145: 1107: 1061: 868: 822: 801:) because we can make 795: 767: 692: 646: 594: 551:Measures of robustness 410:Estimation of location 343:statistical dispersion 326:Described in terms of 8357:Population statistics 8299:System identification 8033:Autocorrelation (ACF) 7961:Exponential smoothing 7875:Discriminant analysis 7870:Canonical correlation 7734:Partition of variance 7596:Regression validation 7440:(Jonckheere–Terpstra) 7339:Likelihood-ratio test 7028:Frequentist inference 6940:Location–scale family 6861:Sampling distribution 6826:Statistical inference 6793:Cross-sectional study 6780:Observational studies 6739:Randomized experiment 6568:Stem-and-leaf display 6370:Central limit theorem 6084:Wilcox, Rand (2012), 5717:10.1002/9781119214656 5337:Maronna et al. (2019) 5262:10.1002/9780470434697 5227:10.1002/9780470434697 5113:multivariate analysis 5046: 4986: 4957: 4860: 4840: 4838:{\displaystyle \psi } 4820: 4800: 4780: 4752: 4723: 4660: 4623:Maronna et al. (2019) 4616: 4614:{\displaystyle \psi } 4592: 4590:{\displaystyle \psi } 4557: 4438: 4409: 4319: 4317:{\displaystyle \psi } 4299: 4297:{\displaystyle \psi } 4279: 4215: 4213:{\displaystyle \rho } 4195: 4156: 4154:{\displaystyle \psi } 4136: 4134:{\displaystyle \rho } 4116: 4114:{\displaystyle \psi } 4096: 4094:{\displaystyle \rho } 4073: 4071:{\displaystyle \rho } 4053: 3992: 3941: 3929: 3927:{\displaystyle \rho } 3909: 3864: 3845: 3843:{\displaystyle \rho } 3825: 3780: 3768: 3714: 3702: 3657: 3611: 3591: 3571: 3551: 3524: 3335: 3225: 3103: 3073: 3043: 3003: 2983: 2960: 2817: 2784: 2782:{\displaystyle \{x\}} 2758: 2731: 2698: 2672: 2652: 2621: 2484: 2464: 2444: 2424: 2401: 2381: 2320: 2272: 2245:. Let the functional 2240: 2220: 2200: 2174: 2154: 2114: 2087: 1820: 1800: 1767: 1728:is an estimator. Let 1723: 1642: 1586: 1496: 1454: 1397: 1352: 1290: 1241: 1207: 1168: 1146: 1108: 1059: 899:resistant statistics. 888:Maronna et al. (2019) 869: 823: 796: 768: 693: 647: 595: 534:first appearing over 386:measurements made by 361:Winsorised estimators 125:parametric statistics 114:sampling distribution 91:central limit theorem 51:regression parameters 8280:Probabilistic design 7865:Principal components 7708:Exponential families 7660:Nonlinear regression 7639:General linear model 7601:Mixed effects models 7591:Errors and residuals 7568:Confounding variable 7470:Bayesian probability 7448:Van der Waerden test 7438:Ordered alternative 7203:Multiple comparisons 7082:Rao–Blackwellization 7045:Estimating equations 7001:Statistical distance 6719:Factorial experiment 6252:Arithmetic-Geometric 6044:, pp. 1514–1519 5560:Annals of Statistics 5348:Resistant statistics 4998: 4969: 4887: 4858:{\displaystyle \nu } 4849: 4829: 4818:{\displaystyle \nu } 4809: 4798:{\displaystyle \nu } 4789: 4778:{\displaystyle \nu } 4769: 4735: 4672: 4658:{\displaystyle \nu } 4649: 4605: 4581: 4450: 4421: 4331: 4308: 4288: 4268: 4204: 4175: 4171:For squared errors, 4145: 4125: 4105: 4085: 4062: 4001: 3938: 3918: 3861: 3834: 3777: 3711: 3654: 3600: 3580: 3560: 3540: 3352: 3242: 3121: 3085: 3055: 3025: 3013:Desirable properties 2992: 2972: 2829: 2793: 2767: 2740: 2710: 2681: 2661: 2641: 2499: 2473: 2453: 2433: 2413: 2390: 2333: 2281: 2249: 2229: 2209: 2183: 2163: 2143: 2103: 1832: 1809: 1776: 1732: 1651: 1599: 1505: 1470: 1407: 1363: 1301: 1257: 1218: 1181: 1157: 1119: 1075: 1018:improve this section 832: 805: 777: 702: 656: 604: 584: 282:resistant statistics 67:normal distributions 8352:Official statistics 8275:Methods engineering 7956:Seasonal adjustment 7724:Poisson regressions 7644:Bayesian regression 7583:Regression analysis 7563:Partial correlation 7535:Regression analysis 7134:Prediction interval 7129:Likelihood interval 7119:Confidence interval 7111:Interval estimation 7072:Unbiased estimators 6890:Model specification 6770:Up-and-down designs 6458:Partial correlation 6414:Index of dispersion 6332:Interquartile range 5999:Stigler, Stephen M. 5939:Rousseeuw, Peter J. 5899:Rousseeuw, Peter J. 5857:Rousseeuw, Peter J. 5505:Rousseeuw, Peter J. 5352:David B. Stephenson 5320:Weather Underground 5132:Masreliez's theorem 5065:ancillary statistic 4645:-distribution with 4284:is proportional to 4222:Huber loss function 4081:Several choices of 4078:has a derivative). 2696:{\displaystyle G-F} 794:{\displaystyle 1/n} 467:Estimation of scale 375:Speed-of-light data 339:interquartile range 246:, as well as being 155:location parameters 71:standard deviations 55:statistical methods 8372:Spatial statistics 8252:Medical statistics 8152:First hitting time 8106:Whittle likelihood 7757:Degrees of freedom 7752:Multivariate ANOVA 7685:Heteroscedasticity 7497:Bayesian estimator 7462:Bayesian inference 7311:Kolmogorov–Smirnov 7196:Randomization test 7166:Testing hypotheses 7139:Tolerance interval 7050:Maximum likelihood 6945:Exponential family 6878:Density estimation 6838:Statistical theory 6798:Natural experiment 6744:Scientific control 6661:Survey methodology 6347:Standard deviation 6140:David Olive's site 5913:10.1002/0471725382 5869:(424): 1273–1283, 5792:Teukolsky, Saul A. 5758:(452): 1331–1335, 5744:Portnoy, Stephen; 5314:Masters, Jeffrey. 5041: 4981: 4952: 4855: 4835: 4815: 4795: 4775: 4763:kurtosis parameter 4747: 4718: 4655: 4611: 4587: 4552: 4433: 4404: 4314: 4294: 4274: 4210: 4190: 4151: 4131: 4111: 4091: 4068: 4048: 3987: 3924: 3904: 3840: 3820: 3763: 3697: 3606: 3596:and remove one at 3586: 3566: 3546: 3534:Lipschitz constant 3519: 3436: 3330: 3292: 3220: 3152: 3098: 3068: 3038: 2998: 2978: 2955: 2884: 2812: 2779: 2753: 2726: 2693: 2667: 2647: 2635:Gateaux derivative 2616: 2555: 2492:We're looking at: 2479: 2459: 2439: 2419: 2396: 2376: 2315: 2267: 2235: 2215: 2205:of a distribution 2195: 2169: 2149: 2109: 2082: 1815: 1795: 1762: 1718: 1637: 1581: 1491: 1449: 1392: 1347: 1285: 1236: 1202: 1163: 1141: 1103: 1062: 864: 818: 791: 763: 688: 642: 590: 561:influence function 491:smoothed bootstrap 357:Trimmed estimators 347:standard deviation 203:. You can help by 106:influence function 27:Type of statistics 8487:Robust statistics 8474: 8473: 8412: 8411: 8408: 8407: 8347:National accounts 8317:Actuarial science 8309:Social statistics 8202: 8201: 8198: 8197: 8194: 8193: 8129:Survival function 8114: 8113: 7976:Granger causality 7817:Contingency table 7792:Survival analysis 7769: 7768: 7765: 7764: 7621:Linear regression 7516: 7515: 7512: 7511: 7487:Credible interval 7456: 7455: 7239: 7238: 7055:Method of moments 6924:Parametric family 6885:Statistical model 6815: 6814: 6811: 6810: 6729:Random assignment 6651:Statistical power 6585: 6584: 6581: 6580: 6430:Contingency table 6400: 6399: 6267:Generalized/power 6103:978-0-12-386983-8 5835:(14): 3402–3410, 5811:978-0-521-88068-8 5788:Press, William H. 5726:978-1-119-21468-7 5664:Robust statistics 5509:Robust statistics 5492:978-1-4665-9062-5 5271:978-0-470-12990-6 5253:Robust Statistics 5236:978-0-470-12990-6 5218:Robust Statistics 5153:Robust regression 5032: 5010: 4943: 4921: 4899: 4713: 4512: 4277:{\displaystyle T} 4046: 3609:{\displaystyle x} 3589:{\displaystyle y} 3569:{\displaystyle y} 3549:{\displaystyle x} 3513: 3434: 3383: 3273: 3137: 3001:{\displaystyle t} 2981:{\displaystyle x} 2950: 2862: 2670:{\displaystyle F} 2650:{\displaystyle T} 2614: 2533: 2482:{\displaystyle G} 2462:{\displaystyle F} 2442:{\displaystyle A} 2422:{\displaystyle G} 2399:{\displaystyle F} 2327:Fisher consistent 2238:{\displaystyle A} 2218:{\displaystyle F} 2152:{\displaystyle A} 2112:{\displaystyle x} 1818:{\displaystyle i} 1054: 1053: 1046: 988: 987: 980: 816: 761: 720: 593:{\displaystyle n} 565:sensitivity curve 392:Classic data sets 271:outlier-resistant 221: 220: 109:described below. 87:model assumptions 31:Robust statistics 16:(Redirected from 8494: 8462: 8461: 8450: 8449: 8439: 8438: 8424: 8423: 8327:Crime statistics 8221: 8208: 8125: 8091:Fourier analysis 8078:Frequency domain 8058: 8005: 7971:Structural break 7931: 7880:Cluster analysis 7827:Log-linear model 7800: 7775: 7716: 7690:Homoscedasticity 7546: 7522: 7441: 7433: 7425: 7424:(Kruskal–Wallis) 7409: 7394: 7349:Cross validation 7334: 7316:Anderson–Darling 7263: 7250: 7221:Likelihood-ratio 7213:Parametric tests 7191:Permutation test 7174:1- & 2-tails 7065:Minimum distance 7037:Point estimation 7033: 6984:Optimal decision 6935: 6834: 6821: 6803:Quasi-experiment 6753:Adaptive designs 6604: 6591: 6468:Rank correlation 6230: 6221: 6208: 6175: 6168: 6161: 6152: 6114: 6079: 6070: 6045: 6035: 5993: 5969: 5933: 5893: 5851: 5822: 5782: 5739: 5729: 5703: 5684: 5654: 5627: 5603:(410): 446–452, 5585: 5576: 5567:(4): 2161–2167, 5550: 5529: 5501:Hampel, Frank R. 5495: 5469: 5463: 5457: 5451: 5445: 5439: 5433: 5427: 5418: 5412: 5406: 5396: 5390: 5384: 5378: 5372: 5366: 5363:von Mises (1947) 5360: 5354: 5345: 5339: 5334: 5328: 5327: 5322:. Archived from 5311: 5305: 5299: 5293: 5287: 5276: 5275: 5247: 5241: 5240: 5212: 5206: 5205: 5173: 5061:pivotal quantity 5055:Related concepts 5050: 5048: 5047: 5042: 5034: 5033: 5025: 5012: 5011: 5003: 4990: 4988: 4987: 4982: 4961: 4959: 4958: 4953: 4945: 4944: 4936: 4923: 4922: 4914: 4901: 4900: 4892: 4872: 4864: 4862: 4861: 4856: 4844: 4842: 4841: 4836: 4824: 4822: 4821: 4816: 4804: 4802: 4801: 4796: 4784: 4782: 4781: 4776: 4756: 4754: 4753: 4748: 4727: 4725: 4724: 4719: 4714: 4712: 4705: 4704: 4691: 4664: 4662: 4661: 4656: 4620: 4618: 4617: 4612: 4596: 4594: 4593: 4588: 4561: 4559: 4558: 4553: 4532: 4531: 4517: 4513: 4511: 4503: 4480: 4473: 4472: 4471: 4442: 4440: 4439: 4434: 4413: 4411: 4410: 4405: 4376: 4375: 4323: 4321: 4320: 4315: 4303: 4301: 4300: 4295: 4283: 4281: 4280: 4275: 4234: 4219: 4217: 4216: 4211: 4199: 4197: 4196: 4191: 4168: 4160: 4158: 4157: 4152: 4140: 4138: 4137: 4132: 4120: 4118: 4117: 4112: 4100: 4098: 4097: 4092: 4077: 4075: 4074: 4069: 4057: 4055: 4054: 4049: 4047: 4045: 4037: 4020: 3996: 3994: 3993: 3988: 3977: 3976: 3960: 3955: 3933: 3931: 3930: 3925: 3913: 3911: 3910: 3905: 3900: 3899: 3883: 3878: 3849: 3847: 3846: 3841: 3829: 3827: 3826: 3821: 3816: 3815: 3799: 3794: 3772: 3770: 3769: 3764: 3759: 3758: 3733: 3728: 3706: 3704: 3703: 3698: 3693: 3692: 3676: 3671: 3615: 3613: 3612: 3607: 3595: 3593: 3592: 3587: 3575: 3573: 3572: 3567: 3555: 3553: 3552: 3547: 3528: 3526: 3525: 3520: 3518: 3514: 3512: 3501: 3442: 3435: 3433: 3422: 3421: 3420: 3415: 3414: 3364: 3363: 3339: 3337: 3336: 3331: 3329: 3297: 3291: 3290: 3289: 3254: 3253: 3229: 3227: 3226: 3221: 3210: 3202: 3151: 3133: 3132: 3107: 3105: 3104: 3099: 3097: 3096: 3077: 3075: 3074: 3069: 3067: 3066: 3047: 3045: 3044: 3039: 3037: 3036: 3007: 3005: 3004: 2999: 2987: 2985: 2984: 2979: 2964: 2962: 2961: 2956: 2951: 2946: 2906: 2905: 2886: 2883: 2882: 2881: 2821: 2819: 2818: 2813: 2811: 2810: 2788: 2786: 2785: 2780: 2762: 2760: 2759: 2754: 2752: 2751: 2735: 2733: 2732: 2727: 2725: 2724: 2702: 2700: 2699: 2694: 2676: 2674: 2673: 2668: 2656: 2654: 2653: 2648: 2625: 2623: 2622: 2617: 2615: 2610: 2557: 2554: 2553: 2552: 2520: 2519: 2488: 2486: 2485: 2480: 2468: 2466: 2465: 2460: 2448: 2446: 2445: 2440: 2428: 2426: 2425: 2420: 2405: 2403: 2402: 2397: 2385: 2383: 2382: 2377: 2366: 2365: 2324: 2322: 2321: 2316: 2314: 2313: 2312: 2296: 2295: 2276: 2274: 2273: 2268: 2244: 2242: 2241: 2236: 2224: 2222: 2221: 2216: 2204: 2202: 2201: 2196: 2178: 2176: 2175: 2170: 2158: 2156: 2155: 2150: 2118: 2116: 2115: 2110: 2091: 2089: 2088: 2083: 2075: 2074: 2056: 2055: 2037: 2036: 2024: 2023: 1999: 1998: 1986: 1985: 1970: 1969: 1951: 1950: 1926: 1925: 1901: 1900: 1888: 1887: 1866: 1865: 1850: 1849: 1824: 1822: 1821: 1816: 1804: 1802: 1801: 1796: 1794: 1793: 1771: 1769: 1768: 1763: 1727: 1725: 1724: 1719: 1696: 1695: 1683: 1682: 1677: 1676: 1663: 1662: 1646: 1644: 1643: 1638: 1633: 1632: 1614: 1613: 1590: 1588: 1587: 1582: 1571: 1570: 1555: 1554: 1536: 1535: 1517: 1516: 1500: 1498: 1497: 1492: 1490: 1489: 1484: 1458: 1456: 1455: 1450: 1445: 1444: 1435: 1401: 1399: 1398: 1393: 1391: 1390: 1385: 1376: 1356: 1354: 1353: 1348: 1343: 1342: 1333: 1313: 1312: 1294: 1292: 1291: 1286: 1275: 1274: 1245: 1243: 1242: 1237: 1211: 1209: 1208: 1203: 1201: 1200: 1195: 1172: 1170: 1169: 1164: 1150: 1148: 1147: 1142: 1131: 1130: 1112: 1110: 1109: 1104: 1093: 1092: 1049: 1042: 1038: 1035: 1029: 998: 990: 983: 976: 972: 969: 963: 943: 942: 935: 873: 871: 870: 865: 863: 862: 844: 843: 827: 825: 824: 819: 817: 809: 800: 798: 797: 792: 787: 772: 770: 769: 764: 762: 757: 756: 755: 737: 736: 726: 721: 716: 715: 706: 697: 695: 694: 689: 687: 686: 668: 667: 651: 649: 648: 643: 638: 637: 619: 618: 599: 597: 596: 591: 500: 452: 328:breakdown points 321:central tendency 310:central tendency 236:robust estimator 216: 213: 195: 188: 161:scale parameters 21: 18:Robust statistic 8502: 8501: 8497: 8496: 8495: 8493: 8492: 8491: 8477: 8476: 8475: 8470: 8433: 8404: 8366: 8303: 8289:quality control 8256: 8238:Clinical trials 8215: 8190: 8174: 8162:Hazard function 8156: 8110: 8072: 8056: 8019: 8015:Breusch–Godfrey 8003: 7980: 7920: 7895:Factor analysis 7841: 7822:Graphical model 7794: 7761: 7728: 7714: 7694: 7648: 7615: 7577: 7540: 7539: 7508: 7452: 7439: 7431: 7423: 7407: 7392: 7371:Rank statistics 7365: 7344:Model selection 7332: 7290:Goodness of fit 7284: 7261: 7235: 7207: 7160: 7105: 7094:Median unbiased 7022: 6933: 6866:Order statistic 6828: 6807: 6774: 6748: 6700: 6655: 6598: 6596:Data collection 6577: 6489: 6444: 6418: 6396: 6356: 6308: 6225:Continuous data 6215: 6202: 6184: 6179: 6122: 6104: 6083: 6049: 6039: 5997: 5976: 5937: 5923: 5897: 5875:10.2307/2291267 5855: 5826: 5812: 5786: 5764:10.2307/2669782 5743: 5738:, Prentice-Hall 5733: 5727: 5706: 5701: 5688: 5674: 5660:Huber, Peter J. 5658: 5644: 5631: 5609:10.2307/2289782 5589: 5553: 5533: 5519: 5499: 5493: 5480: 5477: 5472: 5464: 5460: 5452: 5448: 5440: 5436: 5428: 5421: 5413: 5409: 5397: 5393: 5385: 5381: 5373: 5369: 5361: 5357: 5346: 5342: 5335: 5331: 5313: 5312: 5308: 5300: 5296: 5288: 5279: 5272: 5249: 5248: 5244: 5237: 5214: 5213: 5209: 5175: 5174: 5170: 5166: 5144: 5084: 5078: 5070:test statistics 5057: 4996: 4995: 4967: 4966: 4885: 4884: 4878: 4847: 4846: 4827: 4826: 4807: 4806: 4787: 4786: 4767: 4766: 4733: 4732: 4696: 4695: 4670: 4669: 4647: 4646: 4638:-distribution. 4631: 4603: 4602: 4601:Theoretically, 4579: 4578: 4575: 4504: 4481: 4475: 4474: 4462: 4448: 4447: 4419: 4418: 4364: 4329: 4328: 4306: 4305: 4286: 4285: 4266: 4265: 4262: 4240: 4202: 4201: 4173: 4172: 4143: 4142: 4123: 4122: 4103: 4102: 4083: 4082: 4060: 4059: 4038: 4021: 3999: 3998: 3968: 3936: 3935: 3916: 3915: 3891: 3859: 3858: 3832: 3831: 3807: 3775: 3774: 3750: 3709: 3708: 3684: 3652: 3651: 3628: 3622: 3598: 3597: 3578: 3577: 3558: 3557: 3538: 3537: 3502: 3443: 3437: 3423: 3408: 3389: 3355: 3350: 3349: 3346: 3245: 3240: 3239: 3236: 3124: 3119: 3118: 3115: 3113:Rejection point 3088: 3083: 3082: 3058: 3053: 3052: 3028: 3023: 3022: 3015: 2990: 2989: 2970: 2969: 2897: 2887: 2873: 2827: 2826: 2802: 2791: 2790: 2765: 2764: 2743: 2738: 2737: 2708: 2707: 2679: 2678: 2659: 2658: 2639: 2638: 2558: 2544: 2505: 2497: 2496: 2471: 2470: 2451: 2450: 2431: 2430: 2411: 2410: 2388: 2387: 2357: 2331: 2330: 2297: 2287: 2279: 2278: 2247: 2246: 2227: 2226: 2207: 2206: 2181: 2180: 2161: 2160: 2141: 2140: 2125: 2119:to the sample. 2101: 2100: 2066: 2041: 2028: 2009: 1990: 1977: 1961: 1936: 1911: 1892: 1879: 1841: 1830: 1829: 1825:is defined by: 1807: 1806: 1805:at observation 1785: 1774: 1773: 1730: 1729: 1687: 1670: 1654: 1649: 1648: 1624: 1605: 1597: 1596: 1527: 1508: 1503: 1502: 1479: 1468: 1467: 1405: 1404: 1380: 1361: 1360: 1299: 1298: 1255: 1254: 1216: 1215: 1190: 1179: 1178: 1175:parameter space 1155: 1154: 1117: 1116: 1073: 1072: 1050: 1039: 1033: 1030: 1015: 999: 984: 973: 967: 964: 956:help improve it 953: 944: 940: 933: 931:Cook's distance 927: 906: 854: 835: 830: 829: 803: 802: 775: 774: 747: 728: 727: 707: 700: 699: 678: 659: 654: 653: 629: 610: 602: 601: 582: 581: 573: 571:Breakdown point 557:breakdown point 553: 544: 510: 475: 469: 412: 377: 302: 217: 211: 208: 201:needs expansion 186: 100:breakdown point 83: 69:with different 28: 23: 22: 15: 12: 11: 5: 8500: 8498: 8490: 8489: 8479: 8478: 8472: 8471: 8469: 8468: 8456: 8444: 8430: 8417: 8414: 8413: 8410: 8409: 8406: 8405: 8403: 8402: 8397: 8392: 8387: 8382: 8376: 8374: 8368: 8367: 8365: 8364: 8359: 8354: 8349: 8344: 8339: 8334: 8329: 8324: 8319: 8313: 8311: 8305: 8304: 8302: 8301: 8296: 8291: 8282: 8277: 8272: 8266: 8264: 8258: 8257: 8255: 8254: 8249: 8244: 8235: 8233:Bioinformatics 8229: 8227: 8217: 8216: 8211: 8204: 8203: 8200: 8199: 8196: 8195: 8192: 8191: 8189: 8188: 8182: 8180: 8176: 8175: 8173: 8172: 8166: 8164: 8158: 8157: 8155: 8154: 8149: 8144: 8139: 8133: 8131: 8122: 8116: 8115: 8112: 8111: 8109: 8108: 8103: 8098: 8093: 8088: 8082: 8080: 8074: 8073: 8071: 8070: 8065: 8060: 8052: 8047: 8042: 8041: 8040: 8038:partial (PACF) 8029: 8027: 8021: 8020: 8018: 8017: 8012: 8007: 7999: 7994: 7988: 7986: 7985:Specific tests 7982: 7981: 7979: 7978: 7973: 7968: 7963: 7958: 7953: 7948: 7943: 7937: 7935: 7928: 7922: 7921: 7919: 7918: 7917: 7916: 7915: 7914: 7899: 7898: 7897: 7887: 7885:Classification 7882: 7877: 7872: 7867: 7862: 7857: 7851: 7849: 7843: 7842: 7840: 7839: 7834: 7832:McNemar's test 7829: 7824: 7819: 7814: 7808: 7806: 7796: 7795: 7778: 7771: 7770: 7767: 7766: 7763: 7762: 7760: 7759: 7754: 7749: 7744: 7738: 7736: 7730: 7729: 7727: 7726: 7710: 7704: 7702: 7696: 7695: 7693: 7692: 7687: 7682: 7677: 7672: 7670:Semiparametric 7667: 7662: 7656: 7654: 7650: 7649: 7647: 7646: 7641: 7636: 7631: 7625: 7623: 7617: 7616: 7614: 7613: 7608: 7603: 7598: 7593: 7587: 7585: 7579: 7578: 7576: 7575: 7570: 7565: 7560: 7554: 7552: 7542: 7541: 7538: 7537: 7532: 7526: 7525: 7518: 7517: 7514: 7513: 7510: 7509: 7507: 7506: 7505: 7504: 7494: 7489: 7484: 7483: 7482: 7477: 7466: 7464: 7458: 7457: 7454: 7453: 7451: 7450: 7445: 7444: 7443: 7435: 7427: 7411: 7408:(Mann–Whitney) 7403: 7402: 7401: 7388: 7387: 7386: 7375: 7373: 7367: 7366: 7364: 7363: 7362: 7361: 7356: 7351: 7341: 7336: 7333:(Shapiro–Wilk) 7328: 7323: 7318: 7313: 7308: 7300: 7294: 7292: 7286: 7285: 7283: 7282: 7274: 7265: 7253: 7247: 7245:Specific tests 7241: 7240: 7237: 7236: 7234: 7233: 7228: 7223: 7217: 7215: 7209: 7208: 7206: 7205: 7200: 7199: 7198: 7188: 7187: 7186: 7176: 7170: 7168: 7162: 7161: 7159: 7158: 7157: 7156: 7151: 7141: 7136: 7131: 7126: 7121: 7115: 7113: 7107: 7106: 7104: 7103: 7098: 7097: 7096: 7091: 7090: 7089: 7084: 7069: 7068: 7067: 7062: 7057: 7052: 7041: 7039: 7030: 7024: 7023: 7021: 7020: 7015: 7010: 7009: 7008: 6998: 6993: 6992: 6991: 6981: 6980: 6979: 6974: 6969: 6959: 6954: 6949: 6948: 6947: 6942: 6937: 6921: 6920: 6919: 6914: 6909: 6899: 6898: 6897: 6892: 6882: 6881: 6880: 6870: 6869: 6868: 6858: 6853: 6848: 6842: 6840: 6830: 6829: 6824: 6817: 6816: 6813: 6812: 6809: 6808: 6806: 6805: 6800: 6795: 6790: 6784: 6782: 6776: 6775: 6773: 6772: 6767: 6762: 6756: 6754: 6750: 6749: 6747: 6746: 6741: 6736: 6731: 6726: 6721: 6716: 6710: 6708: 6702: 6701: 6699: 6698: 6696:Standard error 6693: 6688: 6683: 6682: 6681: 6676: 6665: 6663: 6657: 6656: 6654: 6653: 6648: 6643: 6638: 6633: 6628: 6626:Optimal design 6623: 6618: 6612: 6610: 6600: 6599: 6594: 6587: 6586: 6583: 6582: 6579: 6578: 6576: 6575: 6570: 6565: 6560: 6555: 6550: 6545: 6540: 6535: 6530: 6525: 6520: 6515: 6510: 6505: 6499: 6497: 6491: 6490: 6488: 6487: 6482: 6481: 6480: 6475: 6465: 6460: 6454: 6452: 6446: 6445: 6443: 6442: 6437: 6432: 6426: 6424: 6423:Summary tables 6420: 6419: 6417: 6416: 6410: 6408: 6402: 6401: 6398: 6397: 6395: 6394: 6393: 6392: 6387: 6382: 6372: 6366: 6364: 6358: 6357: 6355: 6354: 6349: 6344: 6339: 6334: 6329: 6324: 6318: 6316: 6310: 6309: 6307: 6306: 6301: 6296: 6295: 6294: 6289: 6284: 6279: 6274: 6269: 6264: 6259: 6257:Contraharmonic 6254: 6249: 6238: 6236: 6227: 6217: 6216: 6211: 6204: 6203: 6201: 6200: 6195: 6189: 6186: 6185: 6180: 6178: 6177: 6170: 6163: 6155: 6149: 6148: 6143: 6137: 6131: 6126:Brian Ripley's 6121: 6120:External links 6118: 6117: 6116: 6102: 6081: 6061:(3): 309–348, 6047: 6037: 6011:(4): 277–281, 5995: 5985:(9): 909–916, 5974: 5959:10.1002/widm.2 5935: 5921: 5895: 5853: 5829:Water Research 5824: 5810: 5784: 5741: 5731: 5725: 5704: 5699: 5686: 5672: 5656: 5642: 5629: 5587: 5551: 5531: 5517: 5497: 5491: 5476: 5473: 5471: 5470: 5458: 5446: 5434: 5419: 5407: 5391: 5379: 5367: 5355: 5340: 5329: 5326:on 2016-09-15. 5306: 5294: 5277: 5270: 5242: 5235: 5207: 5167: 5165: 5162: 5161: 5160: 5155: 5150: 5143: 5140: 5124:Kalman filters 5080:Main article: 5077: 5074: 5056: 5053: 5052: 5051: 5040: 5037: 5031: 5028: 5021: 5018: 5015: 5009: 5006: 4980: 4977: 4974: 4963: 4962: 4951: 4948: 4942: 4939: 4932: 4929: 4926: 4920: 4917: 4910: 4907: 4904: 4898: 4895: 4877: 4874: 4854: 4834: 4814: 4794: 4774: 4746: 4743: 4740: 4729: 4728: 4717: 4711: 4708: 4703: 4699: 4694: 4689: 4686: 4683: 4680: 4677: 4654: 4630: 4627: 4610: 4586: 4574: 4564: 4563: 4562: 4551: 4548: 4545: 4542: 4539: 4536: 4530: 4527: 4524: 4521: 4516: 4510: 4507: 4502: 4499: 4496: 4493: 4490: 4487: 4484: 4478: 4470: 4465: 4461: 4458: 4455: 4432: 4429: 4426: 4415: 4414: 4403: 4400: 4397: 4394: 4391: 4388: 4385: 4382: 4379: 4374: 4371: 4367: 4363: 4360: 4357: 4354: 4351: 4348: 4345: 4342: 4339: 4336: 4313: 4293: 4273: 4261: 4258: 4239: 4236: 4209: 4189: 4186: 4183: 4180: 4150: 4130: 4110: 4090: 4067: 4044: 4041: 4036: 4033: 4030: 4027: 4024: 4018: 4015: 4012: 4009: 4006: 3986: 3983: 3980: 3975: 3971: 3967: 3964: 3959: 3954: 3951: 3948: 3944: 3923: 3903: 3898: 3894: 3890: 3887: 3882: 3877: 3874: 3871: 3867: 3839: 3819: 3814: 3810: 3806: 3803: 3798: 3793: 3790: 3787: 3783: 3762: 3757: 3753: 3749: 3746: 3743: 3740: 3737: 3732: 3727: 3724: 3721: 3717: 3696: 3691: 3687: 3683: 3680: 3675: 3670: 3667: 3664: 3660: 3624:Main article: 3621: 3618: 3605: 3585: 3565: 3545: 3530: 3529: 3517: 3511: 3508: 3505: 3500: 3497: 3494: 3491: 3488: 3485: 3482: 3479: 3476: 3473: 3470: 3467: 3464: 3461: 3458: 3455: 3452: 3449: 3446: 3440: 3432: 3429: 3426: 3419: 3413: 3407: 3404: 3401: 3398: 3395: 3392: 3386: 3382: 3379: 3376: 3373: 3370: 3367: 3362: 3358: 3345: 3342: 3341: 3340: 3328: 3324: 3321: 3318: 3315: 3312: 3309: 3306: 3303: 3300: 3296: 3288: 3283: 3280: 3276: 3272: 3269: 3266: 3263: 3260: 3257: 3252: 3248: 3235: 3232: 3231: 3230: 3219: 3216: 3213: 3209: 3205: 3201: 3197: 3194: 3191: 3188: 3185: 3182: 3179: 3176: 3173: 3170: 3167: 3164: 3161: 3158: 3155: 3150: 3147: 3144: 3140: 3136: 3131: 3127: 3114: 3111: 3110: 3109: 3095: 3091: 3079: 3065: 3061: 3049: 3035: 3031: 3014: 3011: 2997: 2977: 2966: 2965: 2954: 2949: 2945: 2942: 2939: 2936: 2933: 2930: 2927: 2924: 2921: 2918: 2915: 2912: 2909: 2904: 2900: 2896: 2893: 2890: 2880: 2876: 2872: 2869: 2865: 2861: 2858: 2855: 2852: 2849: 2846: 2843: 2840: 2837: 2834: 2809: 2805: 2801: 2798: 2778: 2775: 2772: 2750: 2746: 2723: 2718: 2715: 2692: 2689: 2686: 2666: 2646: 2628: 2627: 2613: 2609: 2606: 2603: 2600: 2597: 2594: 2591: 2588: 2585: 2582: 2579: 2576: 2573: 2570: 2567: 2564: 2561: 2551: 2547: 2543: 2540: 2536: 2532: 2529: 2526: 2523: 2518: 2515: 2512: 2508: 2504: 2478: 2458: 2438: 2418: 2395: 2375: 2372: 2369: 2364: 2360: 2356: 2353: 2350: 2347: 2344: 2341: 2338: 2311: 2307: 2304: 2300: 2294: 2290: 2286: 2266: 2263: 2260: 2257: 2254: 2234: 2214: 2194: 2191: 2188: 2168: 2148: 2124: 2121: 2108: 2093: 2092: 2081: 2078: 2073: 2069: 2065: 2062: 2059: 2054: 2051: 2048: 2044: 2040: 2035: 2031: 2027: 2022: 2019: 2016: 2012: 2008: 2005: 2002: 1997: 1993: 1989: 1984: 1980: 1976: 1973: 1968: 1964: 1960: 1957: 1954: 1949: 1946: 1943: 1939: 1935: 1932: 1929: 1924: 1921: 1918: 1914: 1910: 1907: 1904: 1899: 1895: 1891: 1886: 1882: 1878: 1875: 1872: 1869: 1864: 1859: 1856: 1853: 1848: 1844: 1840: 1837: 1814: 1792: 1788: 1784: 1781: 1761: 1758: 1755: 1752: 1749: 1746: 1743: 1740: 1737: 1717: 1714: 1711: 1708: 1705: 1702: 1699: 1694: 1690: 1686: 1681: 1675: 1669: 1666: 1661: 1657: 1636: 1631: 1627: 1623: 1620: 1617: 1612: 1608: 1604: 1580: 1577: 1574: 1569: 1564: 1561: 1558: 1553: 1548: 1545: 1542: 1539: 1534: 1530: 1526: 1523: 1520: 1515: 1511: 1488: 1483: 1478: 1475: 1461: 1460: 1448: 1443: 1438: 1434: 1430: 1427: 1424: 1421: 1418: 1415: 1412: 1402: 1389: 1384: 1379: 1375: 1371: 1368: 1358: 1346: 1341: 1336: 1332: 1328: 1325: 1322: 1319: 1316: 1311: 1306: 1296: 1284: 1281: 1278: 1273: 1268: 1265: 1262: 1248: 1247: 1235: 1232: 1229: 1226: 1223: 1213: 1199: 1194: 1189: 1186: 1162: 1152: 1140: 1137: 1134: 1129: 1124: 1114: 1102: 1099: 1096: 1091: 1086: 1083: 1080: 1052: 1051: 1002: 1000: 993: 986: 985: 947: 945: 938: 926: 923: 905: 902: 861: 857: 853: 850: 847: 842: 838: 815: 812: 790: 786: 782: 760: 754: 750: 746: 743: 740: 735: 731: 724: 719: 714: 710: 685: 681: 677: 674: 671: 666: 662: 641: 636: 632: 628: 625: 622: 617: 613: 609: 589: 572: 569: 552: 549: 543: 540: 509: 506: 487:(Qn) estimator 471:Main article: 468: 465: 411: 408: 384:speed-of-light 376: 373: 301: 298: 219: 218: 198: 196: 185: 182: 181: 180: 169: 163: 157: 147: 146: 132: 82: 79: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 8499: 8488: 8485: 8484: 8482: 8467: 8466: 8457: 8455: 8454: 8445: 8443: 8442: 8437: 8431: 8429: 8428: 8419: 8418: 8415: 8401: 8398: 8396: 8395:Geostatistics 8393: 8391: 8388: 8386: 8383: 8381: 8378: 8377: 8375: 8373: 8369: 8363: 8362:Psychometrics 8360: 8358: 8355: 8353: 8350: 8348: 8345: 8343: 8340: 8338: 8335: 8333: 8330: 8328: 8325: 8323: 8320: 8318: 8315: 8314: 8312: 8310: 8306: 8300: 8297: 8295: 8292: 8290: 8286: 8283: 8281: 8278: 8276: 8273: 8271: 8268: 8267: 8265: 8263: 8259: 8253: 8250: 8248: 8245: 8243: 8239: 8236: 8234: 8231: 8230: 8228: 8226: 8225:Biostatistics 8222: 8218: 8214: 8209: 8205: 8187: 8186:Log-rank test 8184: 8183: 8181: 8177: 8171: 8168: 8167: 8165: 8163: 8159: 8153: 8150: 8148: 8145: 8143: 8140: 8138: 8135: 8134: 8132: 8130: 8126: 8123: 8121: 8117: 8107: 8104: 8102: 8099: 8097: 8094: 8092: 8089: 8087: 8084: 8083: 8081: 8079: 8075: 8069: 8066: 8064: 8061: 8059: 8057:(Box–Jenkins) 8053: 8051: 8048: 8046: 8043: 8039: 8036: 8035: 8034: 8031: 8030: 8028: 8026: 8022: 8016: 8013: 8011: 8010:Durbin–Watson 8008: 8006: 8000: 7998: 7995: 7993: 7992:Dickey–Fuller 7990: 7989: 7987: 7983: 7977: 7974: 7972: 7969: 7967: 7966:Cointegration 7964: 7962: 7959: 7957: 7954: 7952: 7949: 7947: 7944: 7942: 7941:Decomposition 7939: 7938: 7936: 7932: 7929: 7927: 7923: 7913: 7910: 7909: 7908: 7905: 7904: 7903: 7900: 7896: 7893: 7892: 7891: 7888: 7886: 7883: 7881: 7878: 7876: 7873: 7871: 7868: 7866: 7863: 7861: 7858: 7856: 7853: 7852: 7850: 7848: 7844: 7838: 7835: 7833: 7830: 7828: 7825: 7823: 7820: 7818: 7815: 7813: 7812:Cohen's kappa 7810: 7809: 7807: 7805: 7801: 7797: 7793: 7789: 7785: 7781: 7776: 7772: 7758: 7755: 7753: 7750: 7748: 7745: 7743: 7740: 7739: 7737: 7735: 7731: 7725: 7721: 7717: 7711: 7709: 7706: 7705: 7703: 7701: 7697: 7691: 7688: 7686: 7683: 7681: 7678: 7676: 7673: 7671: 7668: 7666: 7665:Nonparametric 7663: 7661: 7658: 7657: 7655: 7651: 7645: 7642: 7640: 7637: 7635: 7632: 7630: 7627: 7626: 7624: 7622: 7618: 7612: 7609: 7607: 7604: 7602: 7599: 7597: 7594: 7592: 7589: 7588: 7586: 7584: 7580: 7574: 7571: 7569: 7566: 7564: 7561: 7559: 7556: 7555: 7553: 7551: 7547: 7543: 7536: 7533: 7531: 7528: 7527: 7523: 7519: 7503: 7500: 7499: 7498: 7495: 7493: 7490: 7488: 7485: 7481: 7478: 7476: 7473: 7472: 7471: 7468: 7467: 7465: 7463: 7459: 7449: 7446: 7442: 7436: 7434: 7428: 7426: 7420: 7419: 7418: 7415: 7414:Nonparametric 7412: 7410: 7404: 7400: 7397: 7396: 7395: 7389: 7385: 7384:Sample median 7382: 7381: 7380: 7377: 7376: 7374: 7372: 7368: 7360: 7357: 7355: 7352: 7350: 7347: 7346: 7345: 7342: 7340: 7337: 7335: 7329: 7327: 7324: 7322: 7319: 7317: 7314: 7312: 7309: 7307: 7305: 7301: 7299: 7296: 7295: 7293: 7291: 7287: 7281: 7279: 7275: 7273: 7271: 7266: 7264: 7259: 7255: 7254: 7251: 7248: 7246: 7242: 7232: 7229: 7227: 7224: 7222: 7219: 7218: 7216: 7214: 7210: 7204: 7201: 7197: 7194: 7193: 7192: 7189: 7185: 7182: 7181: 7180: 7177: 7175: 7172: 7171: 7169: 7167: 7163: 7155: 7152: 7150: 7147: 7146: 7145: 7142: 7140: 7137: 7135: 7132: 7130: 7127: 7125: 7122: 7120: 7117: 7116: 7114: 7112: 7108: 7102: 7099: 7095: 7092: 7088: 7085: 7083: 7080: 7079: 7078: 7075: 7074: 7073: 7070: 7066: 7063: 7061: 7058: 7056: 7053: 7051: 7048: 7047: 7046: 7043: 7042: 7040: 7038: 7034: 7031: 7029: 7025: 7019: 7016: 7014: 7011: 7007: 7004: 7003: 7002: 6999: 6997: 6994: 6990: 6989:loss function 6987: 6986: 6985: 6982: 6978: 6975: 6973: 6970: 6968: 6965: 6964: 6963: 6960: 6958: 6955: 6953: 6950: 6946: 6943: 6941: 6938: 6936: 6930: 6927: 6926: 6925: 6922: 6918: 6915: 6913: 6910: 6908: 6905: 6904: 6903: 6900: 6896: 6893: 6891: 6888: 6887: 6886: 6883: 6879: 6876: 6875: 6874: 6871: 6867: 6864: 6863: 6862: 6859: 6857: 6854: 6852: 6849: 6847: 6844: 6843: 6841: 6839: 6835: 6831: 6827: 6822: 6818: 6804: 6801: 6799: 6796: 6794: 6791: 6789: 6786: 6785: 6783: 6781: 6777: 6771: 6768: 6766: 6763: 6761: 6758: 6757: 6755: 6751: 6745: 6742: 6740: 6737: 6735: 6732: 6730: 6727: 6725: 6722: 6720: 6717: 6715: 6712: 6711: 6709: 6707: 6703: 6697: 6694: 6692: 6691:Questionnaire 6689: 6687: 6684: 6680: 6677: 6675: 6672: 6671: 6670: 6667: 6666: 6664: 6662: 6658: 6652: 6649: 6647: 6644: 6642: 6639: 6637: 6634: 6632: 6629: 6627: 6624: 6622: 6619: 6617: 6614: 6613: 6611: 6609: 6605: 6601: 6597: 6592: 6588: 6574: 6571: 6569: 6566: 6564: 6561: 6559: 6556: 6554: 6551: 6549: 6546: 6544: 6541: 6539: 6536: 6534: 6531: 6529: 6526: 6524: 6521: 6519: 6518:Control chart 6516: 6514: 6511: 6509: 6506: 6504: 6501: 6500: 6498: 6496: 6492: 6486: 6483: 6479: 6476: 6474: 6471: 6470: 6469: 6466: 6464: 6461: 6459: 6456: 6455: 6453: 6451: 6447: 6441: 6438: 6436: 6433: 6431: 6428: 6427: 6425: 6421: 6415: 6412: 6411: 6409: 6407: 6403: 6391: 6388: 6386: 6383: 6381: 6378: 6377: 6376: 6373: 6371: 6368: 6367: 6365: 6363: 6359: 6353: 6350: 6348: 6345: 6343: 6340: 6338: 6335: 6333: 6330: 6328: 6325: 6323: 6320: 6319: 6317: 6315: 6311: 6305: 6302: 6300: 6297: 6293: 6290: 6288: 6285: 6283: 6280: 6278: 6275: 6273: 6270: 6268: 6265: 6263: 6260: 6258: 6255: 6253: 6250: 6248: 6245: 6244: 6243: 6240: 6239: 6237: 6235: 6231: 6228: 6226: 6222: 6218: 6214: 6209: 6205: 6199: 6196: 6194: 6191: 6190: 6187: 6183: 6176: 6171: 6169: 6164: 6162: 6157: 6156: 6153: 6147: 6144: 6141: 6138: 6135: 6132: 6130: 6127: 6124: 6123: 6119: 6113: 6109: 6105: 6099: 6095: 6091: 6087: 6082: 6078: 6074: 6069: 6064: 6060: 6056: 6052: 6051:von Mises, R. 6048: 6043: 6038: 6034: 6030: 6026: 6022: 6018: 6014: 6010: 6006: 6005: 6000: 5996: 5992: 5988: 5984: 5980: 5975: 5973: 5968: 5964: 5960: 5956: 5952: 5948: 5944: 5940: 5936: 5932: 5928: 5924: 5922:0-471-85233-3 5918: 5914: 5910: 5906: 5905: 5900: 5896: 5892: 5888: 5884: 5880: 5876: 5872: 5868: 5864: 5863: 5858: 5854: 5850: 5846: 5842: 5838: 5834: 5830: 5825: 5821: 5817: 5813: 5807: 5803: 5802: 5797: 5793: 5789: 5785: 5781: 5777: 5773: 5769: 5765: 5761: 5757: 5753: 5752: 5747: 5742: 5737: 5732: 5728: 5722: 5718: 5714: 5710: 5705: 5702: 5700:9780412558504 5696: 5692: 5687: 5683: 5679: 5675: 5673:0-471-41805-6 5669: 5665: 5661: 5657: 5653: 5649: 5645: 5643:0-340-54937-8 5639: 5635: 5630: 5626: 5622: 5618: 5614: 5610: 5606: 5602: 5598: 5597: 5592: 5588: 5584: 5580: 5575: 5570: 5566: 5562: 5561: 5556: 5552: 5549: 5545: 5541: 5537: 5532: 5528: 5524: 5520: 5518:0-471-82921-8 5514: 5510: 5506: 5502: 5498: 5494: 5488: 5484: 5479: 5478: 5474: 5467: 5462: 5459: 5455: 5450: 5447: 5443: 5438: 5435: 5431: 5426: 5424: 5420: 5416: 5411: 5408: 5404: 5400: 5395: 5392: 5388: 5383: 5380: 5376: 5371: 5368: 5364: 5359: 5356: 5353: 5349: 5344: 5341: 5338: 5333: 5330: 5325: 5321: 5317: 5310: 5307: 5303: 5298: 5295: 5291: 5286: 5284: 5282: 5278: 5273: 5267: 5263: 5259: 5255: 5254: 5246: 5243: 5238: 5232: 5228: 5224: 5220: 5219: 5211: 5208: 5203: 5199: 5195: 5191: 5187: 5183: 5179: 5172: 5169: 5163: 5159: 5156: 5154: 5151: 5149: 5146: 5145: 5141: 5139: 5135: 5133: 5129: 5125: 5120: 5118: 5114: 5108: 5106: 5101: 5097: 5093: 5089: 5083: 5075: 5073: 5071: 5066: 5062: 5054: 5038: 5035: 5026: 5019: 5016: 5013: 5004: 4994: 4993: 4992: 4978: 4975: 4972: 4949: 4946: 4937: 4930: 4927: 4924: 4915: 4908: 4905: 4902: 4893: 4883: 4882: 4881: 4875: 4873: 4871: 4866: 4852: 4832: 4812: 4792: 4772: 4764: 4760: 4744: 4741: 4738: 4715: 4709: 4706: 4701: 4697: 4692: 4687: 4681: 4675: 4668: 4667: 4666: 4652: 4644: 4639: 4637: 4628: 4626: 4624: 4608: 4599: 4584: 4573: 4569: 4565: 4549: 4543: 4537: 4534: 4525: 4519: 4514: 4508: 4497: 4494: 4491: 4485: 4476: 4463: 4459: 4456: 4453: 4446: 4445: 4444: 4430: 4427: 4424: 4395: 4389: 4386: 4383: 4377: 4372: 4369: 4365: 4361: 4355: 4352: 4349: 4346: 4343: 4337: 4334: 4327: 4326: 4325: 4311: 4291: 4271: 4259: 4257: 4254: 4250: 4246: 4243: 4237: 4235: 4233: 4228: 4225: 4223: 4207: 4184: 4178: 4169: 4167: 4162: 4148: 4128: 4108: 4088: 4079: 4065: 4042: 4039: 4031: 4025: 4022: 4016: 4010: 4004: 3984: 3981: 3973: 3969: 3962: 3957: 3952: 3949: 3946: 3942: 3921: 3896: 3892: 3885: 3880: 3875: 3872: 3869: 3865: 3855: 3853: 3837: 3812: 3808: 3801: 3796: 3791: 3788: 3785: 3781: 3755: 3751: 3744: 3741: 3738: 3735: 3730: 3725: 3722: 3719: 3715: 3689: 3685: 3678: 3673: 3668: 3665: 3662: 3658: 3649: 3644: 3642: 3638: 3633: 3632: 3627: 3619: 3617: 3603: 3583: 3563: 3543: 3535: 3509: 3506: 3503: 3495: 3492: 3489: 3486: 3483: 3477: 3474: 3471: 3465: 3462: 3459: 3456: 3453: 3447: 3444: 3430: 3427: 3424: 3417: 3405: 3399: 3396: 3393: 3380: 3374: 3371: 3368: 3360: 3356: 3348: 3347: 3343: 3319: 3316: 3313: 3310: 3307: 3301: 3298: 3281: 3278: 3270: 3264: 3261: 3258: 3250: 3246: 3238: 3237: 3233: 3214: 3211: 3203: 3195: 3192: 3189: 3183: 3180: 3177: 3174: 3171: 3165: 3162: 3159: 3156: 3148: 3145: 3142: 3134: 3129: 3125: 3117: 3116: 3112: 3093: 3089: 3080: 3063: 3059: 3050: 3033: 3029: 3020: 3019: 3018: 3012: 3010: 2995: 2975: 2952: 2947: 2940: 2934: 2931: 2925: 2919: 2916: 2913: 2907: 2902: 2894: 2888: 2878: 2874: 2867: 2859: 2853: 2850: 2847: 2844: 2841: 2835: 2832: 2825: 2824: 2823: 2807: 2799: 2796: 2773: 2748: 2716: 2713: 2704: 2690: 2687: 2684: 2664: 2644: 2636: 2633: 2630:which is the 2611: 2604: 2598: 2595: 2589: 2583: 2580: 2577: 2571: 2568: 2565: 2559: 2549: 2545: 2538: 2530: 2524: 2516: 2513: 2510: 2506: 2502: 2495: 2494: 2493: 2490: 2476: 2456: 2436: 2416: 2407: 2393: 2373: 2370: 2362: 2358: 2351: 2348: 2342: 2339: 2328: 2305: 2302: 2292: 2288: 2258: 2255: 2252: 2232: 2212: 2189: 2186: 2146: 2137: 2135: 2131: 2130:distribution, 2122: 2120: 2106: 2098: 2071: 2067: 2063: 2060: 2057: 2052: 2049: 2046: 2042: 2038: 2033: 2029: 2025: 2020: 2017: 2014: 2010: 2006: 2003: 2000: 1995: 1991: 1982: 1978: 1974: 1966: 1962: 1958: 1955: 1952: 1947: 1944: 1941: 1937: 1933: 1930: 1927: 1922: 1919: 1916: 1912: 1908: 1905: 1902: 1897: 1893: 1884: 1880: 1873: 1870: 1857: 1854: 1851: 1846: 1842: 1838: 1835: 1828: 1827: 1826: 1812: 1790: 1786: 1782: 1779: 1756: 1753: 1750: 1747: 1744: 1738: 1735: 1712: 1709: 1692: 1684: 1679: 1664: 1659: 1655: 1629: 1625: 1621: 1618: 1615: 1610: 1606: 1594: 1572: 1546: 1537: 1532: 1528: 1524: 1521: 1518: 1513: 1509: 1486: 1476: 1473: 1464: 1436: 1425: 1419: 1416: 1403: 1387: 1377: 1369: 1359: 1334: 1323: 1314: 1297: 1279: 1276: 1266: 1253: 1252: 1251: 1250:For example, 1230: 1227: 1214: 1197: 1187: 1184: 1177:of dimension 1176: 1153: 1132: 1115: 1097: 1094: 1084: 1071: 1070: 1069: 1066: 1058: 1048: 1045: 1037: 1034:February 2012 1027: 1023: 1019: 1013: 1012: 1008: 1003:This section 1001: 997: 992: 991: 982: 979: 971: 961: 957: 951: 948:This article 946: 937: 936: 932: 924: 922: 918: 914: 912: 903: 901: 900: 895: 893: 889: 885: 881: 878:distribution 875: 859: 855: 851: 848: 845: 840: 836: 810: 788: 784: 780: 758: 752: 748: 744: 741: 738: 733: 729: 722: 712: 708: 698:, we can use 683: 679: 675: 672: 669: 664: 660: 634: 630: 626: 623: 620: 615: 611: 587: 578: 570: 568: 566: 562: 558: 550: 548: 541: 539: 537: 533: 528: 526: 521: 517: 515: 507: 505: 501: 499: 494: 492: 488: 484: 479: 474: 466: 464: 462: 457: 453: 451: 446: 442: 440: 436: 432: 431:from each end 428: 423: 421: 417: 409: 407: 405: 399: 395: 393: 389: 388:Simon Newcomb 385: 381: 374: 372: 370: 366: 362: 358: 354: 352: 348: 344: 340: 336: 331: 329: 324: 322: 318: 313: 311: 307: 299: 297: 295: 291: 286: 283: 278: 276: 272: 268: 262: 260: 256: 251: 249: 245: 241: 237: 233: 232: 226: 215: 206: 202: 199:This section 197: 194: 190: 189: 183: 178: 177:Kalman filter 174: 170: 168: 164: 162: 158: 156: 152: 151: 150: 144: 140: 139:-distribution 138: 133: 130: 129: 128: 126: 121: 119: 118:mixture model 115: 110: 108: 107: 102: 101: 96: 92: 88: 80: 78: 77:work poorly. 76: 72: 68: 64: 60: 56: 52: 48: 44: 40: 36: 32: 19: 8463: 8451: 8432: 8425: 8337:Econometrics 8287: / 8270:Chemometrics 8247:Epidemiology 8240: / 8213:Applications 8055:ARIMA model 8002:Q-statistic 7951:Stationarity 7847:Multivariate 7790: / 7786: / 7784:Multivariate 7782: / 7722: / 7718: / 7492:Bayes factor 7391:Signed rank 7303: 7277: 7269: 7257: 7017: 6952:Completeness 6788:Cohort study 6686:Opinion poll 6621:Missing data 6608:Study design 6563:Scatter plot 6485:Scatter plot 6478:Spearman's ρ 6440:Grouped data 6085: 6058: 6054: 6041: 6008: 6002: 5982: 5978: 5953:(1): 73–79, 5950: 5946: 5903: 5866: 5860: 5832: 5828: 5800: 5755: 5749: 5735: 5708: 5690: 5663: 5633: 5600: 5594: 5564: 5558: 5539: 5535: 5508: 5482: 5461: 5449: 5437: 5410: 5394: 5387:Huber (1981) 5382: 5375:Huber (1981) 5370: 5358: 5343: 5332: 5324:the original 5319: 5309: 5297: 5290:Huber (1981) 5252: 5245: 5217: 5210: 5185: 5181: 5171: 5136: 5121: 5109: 5088:missing data 5085: 5058: 4964: 4879: 4867: 4762: 4758: 4730: 4642: 4640: 4635: 4632: 4600: 4576: 4571: 4567: 4416: 4263: 4255: 4251: 4247: 4244: 4241: 4229: 4226: 4170: 4163: 4080: 3934:and solving 3856: 3851: 3645: 3641:Huber (1981) 3637:L-estimators 3634: 3630: 3629: 3620:M-estimators 3531: 3016: 2967: 2789:. We choose 2705: 2629: 2491: 2408: 2138: 2133: 2129: 2126: 2096: 2094: 1465: 1462: 1249: 1067: 1063: 1040: 1031: 1016:Please help 1004: 974: 965: 949: 919: 915: 907: 898: 896: 884:Huber (1981) 876: 574: 564: 560: 556: 554: 545: 529: 522: 518: 511: 502: 495: 480: 476: 461:M-estimators 458: 454: 447: 443: 430: 427:trimmed mean 424: 413: 400: 396: 378: 369:M-estimators 365:L-estimators 355: 345:, while the 332: 325: 314: 303: 293: 289: 287: 281: 279: 270: 266: 263: 254: 252: 235: 228: 222: 209: 205:adding to it 200: 148: 136: 122: 111: 104: 98: 84: 81:Introduction 30: 29: 8465:WikiProject 8380:Cartography 8342:Jurimetrics 8294:Reliability 8025:Time domain 8004:(Ljung–Box) 7926:Time-series 7804:Categorical 7788:Time-series 7780:Categorical 7715:(Bernoulli) 7550:Correlation 7530:Correlation 7326:Jarque–Bera 7298:Chi-squared 7060:M-estimator 7013:Asymptotics 6957:Sufficiency 6724:Interaction 6636:Replication 6616:Effect size 6573:Violin plot 6553:Radar chart 6533:Forest plot 6523:Correlogram 6473:Kendall's τ 5943:Hubert, Mia 5105:Winsorizing 4161:functions. 3857:Minimizing 3626:M-estimator 2134:sample set, 437:and 10,000 404:inefficient 173:state-space 165:estimating 159:estimating 153:estimating 39:statistical 8332:Demography 8050:ARMA model 7855:Regression 7432:(Friedman) 7393:(Wilcoxon) 7331:Normality 7321:Lilliefors 7268:Student's 7144:Resampling 7018:Robustness 7006:divergence 6996:Efficiency 6934:(monotone) 6929:Likelihood 6846:Population 6679:Stratified 6631:Population 6450:Dependence 6406:Count data 6337:Percentile 6314:Dispersion 6247:Arithmetic 6182:Statistics 5746:He, Xuming 5591:He, Xuming 5555:He, Xuming 5475:References 5092:imputation 5090:is called 5086:Replacing 4566:Choice of 4443:given by: 4324:function. 929:See also: 536:Antarctica 532:ozone hole 525:regression 240:efficiency 184:Definition 95:estimators 35:statistics 7713:Logistic 7480:posterior 7406:Rank sum 7154:Jackknife 7149:Bootstrap 6967:Bootstrap 6902:Parameter 6851:Statistic 6646:Statistic 6558:Run chart 6543:Pie chart 6538:Histogram 6528:Fan chart 6503:Bar chart 6385:L-moments 6272:Geometric 5377:, page 45 5292:, page 1. 5202:0378-3758 5188:: 20–37. 5122:Standard 5030:^ 5027:σ 5008:^ 5005:μ 4973:ν 4941:^ 4938:ν 4919:^ 4916:σ 4897:^ 4894:μ 4853:ν 4833:ψ 4813:ν 4793:ν 4773:ν 4739:ν 4710:ν 4676:ψ 4653:ν 4609:ψ 4585:ψ 4509:θ 4506:∂ 4498:θ 4486:ψ 4483:∂ 4464:∫ 4460:− 4428:× 4417:with the 4378:ψ 4370:− 4312:ψ 4292:ψ 4208:ρ 4179:ρ 4149:ψ 4129:ρ 4109:ψ 4089:ρ 4066:ρ 4026:ρ 4005:ψ 3963:ψ 3943:∑ 3922:ρ 3886:ρ 3866:∑ 3838:ρ 3802:ρ 3782:∑ 3742:⁡ 3736:− 3716:∑ 3659:∏ 3507:− 3472:− 3428:≠ 3406:∈ 3361:∗ 3357:λ 3282:∈ 3251:∗ 3247:γ 3130:∗ 3126:ρ 3094:∗ 3090:λ 3064:∗ 3060:γ 3034:∗ 3030:ρ 2932:− 2917:− 2899:Δ 2871:→ 2804:Δ 2745:Δ 2717:∈ 2688:− 2632:one-sided 2596:− 2581:− 2542:→ 2514:− 2374:θ 2363:θ 2346:Θ 2343:∈ 2340:θ 2337:∀ 2306:∈ 2265:Γ 2262:→ 2193:Θ 2190:∈ 2187:θ 2167:Σ 2061:… 2018:− 2004:… 1975:− 1956:… 1920:− 1906:… 1874:⋅ 1868:↦ 1858:∈ 1751:… 1739:∈ 1707:Γ 1701:→ 1689:Σ 1619:… 1576:Σ 1560:→ 1544:Ω 1522:… 1487:∗ 1477:∈ 1414:Γ 1378:× 1367:Θ 1318:Σ 1264:Ω 1225:Γ 1198:∗ 1188:∈ 1161:Θ 1136:Σ 1082:Ω 1005:does not 968:June 2010 849:… 814:¯ 742:⋯ 718:¯ 673:… 624:… 577:estimator 439:bootstrap 353:are not. 231:statistic 225:statistic 212:July 2008 8481:Category 8427:Category 8120:Survival 7997:Johansen 7720:Binomial 7675:Isotonic 7262:(normal) 6907:location 6714:Blocking 6669:Sampling 6548:Q–Q plot 6513:Box plot 6495:Graphics 6390:Skewness 6380:Kurtosis 6352:Variance 6282:Heronian 6277:Harmonic 6033:10728417 5972:Preprint 5967:17448982 5849:11547861 5662:(1981), 5142:See also 5100:outliers 4641:For the 3997:, where 3830:, where 3516:‖ 3439:‖ 911:outliers 563:and the 514:outliers 420:Q–Q plot 416:rug plot 300:Examples 294:replaces 259:outliers 103:and the 59:outliers 43:location 8453:Commons 8400:Kriging 8285:Process 8242:studies 8101:Wavelet 7934:General 7101:Plug-in 6895:L space 6674:Cluster 6375:Moments 6193:Outline 6112:3286430 6077:0022330 6025:2758558 5931:0914792 5891:1245360 5883:2291267 5820:2371990 5780:1825288 5772:2669782 5682:0606374 5652:1604954 5625:1141746 5617:2289782 5583:1193333 5548:1391639 5527:0829458 4965:Fixing 2329:, i.e. 1026:removed 1011:sources 954:Please 229:robust 143:mixture 123:Robust 8322:Census 7912:Normal 7860:Manova 7680:Robust 7430:2-way 7422:1-way 7260:-test 6931:  6508:Biplot 6299:Median 6292:Lehmer 6234:Center 6110:  6100:  6075:  6031:  6023:  5965:  5929:  5919:  5889:  5881:  5847:  5818:  5808:  5778:  5770:  5723:  5697:  5680:  5670:  5650:  5640:  5623:  5615:  5581:  5546:  5525:  5515:  5489:  5268:  5233:  5200:  4757:, the 1593:i.i.d. 559:, the 380:Gelman 317:median 75:t-test 49:, and 7946:Trend 7475:prior 7417:anova 7306:-test 7280:-test 7272:-test 7179:Power 7124:Pivot 6917:shape 6912:scale 6362:Shape 6342:Range 6287:Heinz 6262:Cubic 6198:Index 6029:S2CID 5963:S2CID 5879:JSTOR 5768:JSTOR 5613:JSTOR 5544:JSTOR 5164:Notes 5039:4.51. 5017:27.49 4950:2.13. 4906:27.40 1173:is a 351:range 290:added 47:scale 8179:Test 7379:Sign 7231:Wald 6304:Mode 6242:Mean 6098:ISBN 5917:ISBN 5845:PMID 5806:ISBN 5721:ISBN 5695:ISBN 5668:ISBN 5638:ISBN 5513:ISBN 5487:ISBN 5266:ISBN 5231:ISBN 5198:ISSN 4928:3.81 4731:For 4570:and 4101:and 4058:(if 3212:> 3146:> 2706:Let 2409:Let 2139:Let 1595:and 1591:are 1501:and 1466:Let 1009:any 1007:cite 886:and 359:and 349:and 337:and 333:The 315:The 306:mean 304:The 269:and 244:bias 33:are 7359:BIC 7354:AIC 6090:doi 6063:doi 6013:doi 5987:doi 5983:133 5955:doi 5909:doi 5871:doi 5837:doi 5760:doi 5713:doi 5605:doi 5569:doi 5258:doi 5223:doi 5190:doi 5186:148 3739:log 3385:sup 3275:sup 3139:inf 2864:lim 2657:at 2637:of 2535:lim 2225:in 1020:by 958:to 207:. 8483:: 6108:MR 6106:, 6096:, 6073:MR 6071:, 6059:18 6057:, 6027:, 6021:MR 6019:, 6009:64 6007:, 5981:, 5970:. 5961:, 5949:, 5941:; 5927:MR 5925:, 5915:, 5887:MR 5885:, 5877:, 5867:88 5865:, 5843:, 5833:35 5831:, 5816:MR 5814:, 5798:, 5790:; 5776:MR 5774:, 5766:, 5756:95 5754:, 5719:, 5678:MR 5676:, 5648:MR 5646:, 5621:MR 5619:, 5611:, 5601:85 5599:, 5579:MR 5577:, 5565:20 5563:, 5538:, 5523:MR 5521:, 5422:^ 5401:; 5350:, 5318:. 5280:^ 5264:. 5229:. 5196:. 5184:. 5180:. 5059:A 4865:. 4224:. 3643:. 3616:. 3381::= 3271::= 3135::= 2860::= 2736:. 2703:. 2489:? 894:. 874:. 723::= 567:. 277:. 45:, 7304:G 7278:F 7270:t 7258:Z 6977:V 6972:U 6174:e 6167:t 6160:v 6115:. 6092:: 6080:. 6065:: 6046:. 6036:. 6015:: 5994:. 5989:: 5957:: 5951:1 5911:: 5894:. 5873:: 5852:. 5839:: 5823:. 5783:. 5762:: 5740:. 5730:. 5715:: 5628:. 5607:: 5586:. 5571:: 5540:7 5496:. 5468:. 5456:. 5444:. 5432:. 5417:. 5405:. 5389:. 5365:. 5304:. 5274:. 5260:: 5239:. 5225:: 5204:. 5192:: 5036:= 5020:, 5014:= 4979:4 4976:= 4947:= 4931:, 4925:= 4909:, 4903:= 4759:t 4745:1 4742:= 4716:. 4707:+ 4702:2 4698:x 4693:x 4688:= 4685:) 4682:x 4679:( 4643:t 4636:t 4572:ρ 4568:ψ 4550:. 4547:) 4544:x 4541:( 4538:F 4535:d 4529:) 4526:F 4523:( 4520:T 4515:) 4501:) 4495:, 4492:x 4489:( 4477:( 4469:X 4457:= 4454:M 4431:p 4425:p 4402:) 4399:) 4396:F 4393:( 4390:T 4387:, 4384:x 4381:( 4373:1 4366:M 4362:= 4359:) 4356:F 4353:, 4350:T 4347:; 4344:x 4341:( 4338:F 4335:I 4272:T 4188:) 4185:x 4182:( 4043:x 4040:d 4035:) 4032:x 4029:( 4023:d 4017:= 4014:) 4011:x 4008:( 3985:0 3982:= 3979:) 3974:i 3970:x 3966:( 3958:n 3953:1 3950:= 3947:i 3902:) 3897:i 3893:x 3889:( 3881:n 3876:1 3873:= 3870:i 3852:M 3818:) 3813:i 3809:x 3805:( 3797:n 3792:1 3789:= 3786:i 3761:) 3756:i 3752:x 3748:( 3745:f 3731:n 3726:1 3723:= 3720:i 3695:) 3690:i 3686:x 3682:( 3679:f 3674:n 3669:1 3666:= 3663:i 3604:x 3584:y 3564:y 3544:x 3510:x 3504:y 3499:) 3496:F 3493:; 3490:T 3487:; 3484:x 3481:( 3478:F 3475:I 3469:) 3466:F 3463:; 3460:T 3457:; 3454:y 3451:( 3448:F 3445:I 3431:y 3425:x 3418:2 3412:X 3403:) 3400:y 3397:, 3394:x 3391:( 3378:) 3375:F 3372:; 3369:T 3366:( 3327:| 3323:) 3320:F 3317:; 3314:T 3311:; 3308:x 3305:( 3302:F 3299:I 3295:| 3287:X 3279:x 3268:) 3265:F 3262:; 3259:T 3256:( 3218:} 3215:r 3208:| 3204:x 3200:| 3196:, 3193:0 3190:= 3187:) 3184:F 3181:; 3178:T 3175:; 3172:x 3169:( 3166:F 3163:I 3160:: 3157:r 3154:{ 3149:0 3143:r 3108:. 3078:, 3048:, 2996:t 2976:x 2953:. 2948:t 2944:) 2941:F 2938:( 2935:T 2929:) 2926:F 2923:) 2920:t 2914:1 2911:( 2908:+ 2903:x 2895:t 2892:( 2889:T 2879:+ 2875:0 2868:t 2857:) 2854:F 2851:; 2848:T 2845:; 2842:x 2839:( 2836:F 2833:I 2808:x 2800:= 2797:G 2777:} 2774:x 2771:{ 2749:x 2722:X 2714:x 2691:F 2685:G 2665:F 2645:T 2626:, 2612:t 2608:) 2605:F 2602:( 2599:T 2593:) 2590:F 2587:) 2584:t 2578:1 2575:( 2572:+ 2569:G 2566:t 2563:( 2560:T 2550:+ 2546:0 2539:t 2531:= 2528:) 2525:F 2522:( 2517:F 2511:G 2507:T 2503:d 2477:G 2457:F 2437:A 2417:G 2394:F 2371:= 2368:) 2359:F 2355:( 2352:T 2349:, 2310:N 2303:n 2299:) 2293:n 2289:T 2285:( 2259:A 2256:: 2253:T 2233:A 2213:F 2147:A 2107:x 2097:i 2080:) 2077:) 2072:n 2068:x 2064:, 2058:, 2053:1 2050:+ 2047:i 2043:x 2039:, 2034:i 2030:x 2026:, 2021:1 2015:i 2011:x 2007:, 2001:, 1996:1 1992:x 1988:( 1983:n 1979:T 1972:) 1967:n 1963:x 1959:, 1953:, 1948:1 1945:+ 1942:i 1938:x 1934:, 1931:x 1928:, 1923:1 1917:i 1913:x 1909:, 1903:, 1898:1 1894:x 1890:( 1885:n 1881:T 1877:( 1871:n 1863:X 1855:x 1852:: 1847:i 1843:F 1839:I 1836:E 1813:i 1791:i 1787:F 1783:I 1780:E 1760:} 1757:n 1754:, 1748:, 1745:1 1742:{ 1736:i 1716:) 1713:S 1710:, 1704:( 1698:) 1693:n 1685:, 1680:n 1674:X 1668:( 1665:: 1660:n 1656:T 1635:) 1630:n 1626:x 1622:, 1616:, 1611:1 1607:x 1603:( 1579:) 1573:, 1568:X 1563:( 1557:) 1552:A 1547:, 1541:( 1538:: 1533:n 1529:X 1525:, 1519:, 1514:1 1510:X 1482:N 1474:n 1459:, 1447:) 1442:B 1437:, 1433:R 1429:( 1426:= 1423:) 1420:S 1417:, 1411:( 1388:+ 1383:R 1374:R 1370:= 1357:, 1345:) 1340:B 1335:, 1331:R 1327:( 1324:= 1321:) 1315:, 1310:X 1305:( 1283:) 1280:P 1277:, 1272:A 1267:, 1261:( 1234:) 1231:S 1228:, 1222:( 1212:, 1193:N 1185:p 1139:) 1133:, 1128:X 1123:( 1101:) 1098:P 1095:, 1090:A 1085:, 1079:( 1047:) 1041:( 1036:) 1032:( 1028:. 1014:. 981:) 975:( 970:) 966:( 952:. 860:n 856:x 852:, 846:, 841:1 837:x 811:x 789:n 785:/ 781:1 759:n 753:n 749:X 745:+ 739:+ 734:1 730:X 713:n 709:X 684:n 680:x 676:, 670:, 665:1 661:x 640:) 635:n 631:X 627:, 621:, 616:1 612:X 608:( 588:n 435:R 214:) 210:( 179:. 137:t 20:)

Index

Robust statistic
statistics
statistical
location
scale
regression parameters
statistical methods
outliers
parametric distribution
normal distributions
standard deviations
t-test
model assumptions
central limit theorem
estimators
breakdown point
influence function
sampling distribution
mixture model
parametric statistics
t-distribution
mixture
location parameters
scale parameters
regression coefficients
state-space
Kalman filter

adding to it
statistic

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑