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Microarray analysis techniques

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209:, can also be applied. Given the number of distance measures available and their influence in the clustering algorithm results, several studies have compared and evaluated different distance measures for the clustering of microarray data, considering their intrinsic properties and robustness to noise. After calculation of the initial distance matrix, the hierarchical clustering algorithm either (A) joins iteratively the two closest clusters starting from single data points (agglomerative, bottom-up approach, which is fairly more commonly used), or (B) partitions clusters iteratively starting from the complete set (divisive, top-down approach). After each step, a new distance matrix between the newly formed clusters and the other clusters is recalculated. Hierarchical cluster analysis methods include: 76: 63: 155:
observation, since the point of performing experiments has to do with predicting general behavior. The MAQC group recommends using a fold change assessment plus a non-stringent p-value cutoff, further pointing out that changes in the background correction and scaling process have only a minimal impact on the rank order of fold change differences, but a substantial impact on p-values.
318:. Protein complex enrichment analysis tool (COMPLEAT) provides similar enrichment analysis at the level of protein complexes. The tool can identify the dynamic protein complex regulation under different condition or time points. Related system, PAINT and SCOPE performs a statistical analysis on gene promoter regions, identifying over and under representation of previously identified 28: 982:(t) are specified to guarantee genes called significant change at least a pre-specified amount. This means that the absolute value of the average expression levels of a gene under each of two conditions must be greater than the fold change (t) to be called positive and less than the inverse of the fold change (t) to be called negative. 290: 975: 50: – in a single experiment. Such experiments can generate very large amounts of data, allowing researchers to assess the overall state of a cell or organism. Data in such large quantities is difficult – if not impossible – to analyze without the help of computer programs. 340: 114:
Raw Affy data contains about twenty probes for the same RNA target. Half of these are "mismatch spots", which do not precisely match the target sequence. These can theoretically measure the amount of nonspecific binding for a given target. Robust Multi-array Average (RMA) is a normalization approach
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response elements. Another statistical analysis tool is Rank Sum Statistics for Gene Set Collections (RssGsc), which uses rank sum probability distribution functions to find gene sets that explain experimental data. A further approach is contextual meta-analysis, i.e. finding out how a gene cluster
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for Robust Microarray Summarization (FARMS) is a model-based technique for summarizing array data at perfect match probe level. It is based on a factor analysis model for which a Bayesian maximum a posteriori method optimizes the model parameters under the assumption of Gaussian measurement noise.
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Microarray data analysis is the final step in reading and processing data produced by a microarray chip. Samples undergo various processes including purification and scanning using the microchip, which then produces a large amount of data that requires processing via computer software. It involves
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Visual identification of local artifacts, such as printing or washing defects, may likewise suggest the removal of individual spots. This can take a substantial amount of time depending on the quality of array manufacture. In addition, some procedures call for the elimination of all spots with an
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Depending on the type of array, signal related to nonspecific binding of the fluorophore can be subtracted to achieve better results. One approach involves subtracting the average signal intensity of the area between spots. A variety of tools for background correction and further analysis are
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or other mechanisms that take both effect size and variability into account. Curiously, the p-values associated with particular genes do not reproduce well between replicate experiments, and lists generated by straight fold change perform much better. This represents an extremely important
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Many strategies exist to identify array probes that show an unusual level of over-expression or under-expression. The simplest one is to call "significant" any probe that differs by an average of at least twofold between treatment groups. More sophisticated approaches are often related to
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several distinct steps, as outlined in the image below. Changing any one of the steps will change the outcome of the analysis, so the MAQC Project was created to identify a set of standard strategies. Companies exist that use the MAQC protocols to perform a complete analysis.
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Comparing two different arrays or two different samples hybridized to the same array generally involves making adjustments for systematic errors introduced by differences in procedures and dye intensity effects. Dye normalization for two color arrays is often achieved by
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Specialized software tools for statistical analysis to determine the extent of over- or under-expression of a gene in a microarray experiment relative to a reference state have also been developed to aid in identifying genes or gene sets associated with particular
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Blocks are batches of microarrays; for example for eight samples split into two groups (control and affected) there are 4!=24 permutations for each block and the total number of permutations is (24)(24)= 576. A minimum of 1000 permutations are
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SAM is run as an Excel Add-In, and the SAM Plot Controller allows Customization of the False Discovery Rate and Delta, while the SAM Plot and SAM Output functionality generate a List of Significant Genes, Delta Table, and Assessment of Sample
369:, it is now possible to measure the expression of thousands of genes in a single hybridization experiment. The data generated is considerable, and a method for sorting out what is significant and what isn't is essential. SAM is distributed by 1071:
Entire arrays may have obvious flaws detectable by visual inspection, pairwise comparisons to arrays in the same experimental group, or by analysis of RNA degradation. Results may improve by removing these arrays from the analysis entirely.
310:-style statistic to identify groups of genes that are regulated together. This third-party statistics package offers the user information on the genes or gene sets of interest, including links to entries in databases such as NCBI's 556:
SAM calculates a test statistic for relative difference in gene expression based on permutation analysis of expression data and calculates a false discovery rate. The principal calculations of the program are illustrated below.
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Commercial systems for gene network analysis such as Ingenuity and Pathway studio create visual representations of differentially expressed genes based on current scientific literature. Non-commercial tools such as FunRich,
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Adjust the Delta tuning parameter to get a significant # of genes along with an acceptable false discovery rate (FDR)) and Assess Sample Size by calculating the mean difference in expression in the SAM Plot
107:. LIMMA provides a set of tools for background correction and scaling, as well as an option to average on-slide duplicate spots. A common method for evaluating how well normalized an array is, is to plot an 227:
Different studies have already shown empirically that the Single linkage clustering algorithm produces poor results when employed to gene expression microarray data and thus should be avoided.
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Jaskowiak, Pablo A.; Campello, Ricardo J.G.B.; Costa, Ivan G. (2013). "Proximity Measures for Clustering Gene Expression Microarray Data: A Validation Methodology and a Comparative Analysis".
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of the data are used to determine if the expression of any gene is significant related to the response. The use of permutation-based analysis accounts for correlations in genes and avoids
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also aid in organizing and visualizing gene network data procured from one or several microarray experiments. A wide variety of microarray analysis tools are available through
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is a public tool to perform contextual meta-analysis across contexts such as anatomical parts, stages of development, and response to diseases, chemicals, stresses, and
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Call each gene significant if the absolute value of the test statistic for that gene minus the mean test statistic for that gene is greater than a stated threshold
2188:"Integration of statistical inference methods and a novel control measure to improve sensitivity and specificity of data analysis in expression profiling studies" 194: 547:— no explicit response parameter is specified; the user specifies eigengene (principal component) of the expression data and treats it as a quantitative response 2243:<Zhang, S. (2007). "A comprehensive evaluation of SAM, the SAM R-package and a simple modification to improve its performance." BMC Bioinformatics 8: 230. 249:. Thus the purpose of K-means clustering is to classify data based on similar expression. K-means clustering algorithm and some of its variants (including 126:
The current Affymetrix MAS5 algorithm, which uses both perfect match and mismatch probes, continues to enjoy popularity and do well in head to head tests.
79: 2554: 198: 286:. The frequently cited SAM module and other microarray tools are available through Stanford University. Another set is available from Harvard and MIT. 253:) have been shown to produce good results for gene expression data (at least better than hierarchical clustering methods). Empirical comparisons of 46:, which allow researchers to investigate the expression state of a large number of genes – in many cases, an organism's entire 1700: 1112: 2620: 1648:
Guo L, Lobenhofer EK, Wang C, et al. (2006). "Rat toxicogenomic study reveals analytical consistency across microarray platforms".
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Chu, G., Narasimhan, B, Tibshirani, R, Tusher, V. "SAM "Significance Analysis of Microarrays" Users Guide and technical document."
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According to the Affycomp benchmark FARMS outperformed all other summarizations methods with respect to sensitivity and specificity.
1907: 1238: 2047: 562: 1601:"The MicroArray Quality Control (MAQC) project shows inter- and intraplatform reproducibility of gene expression measurements" 567: 75: 123:, also part of RMA, is one sensible approach to normalize a batch of arrays in order to make further comparisons meaningful. 515:— measurement units are different in the two groups; e.g. control and treatment groups with samples from different patients 245:
groups. Grouping is done by minimizing the sum of the squares of distances between the data and the corresponding cluster
186: 541:— each experimental units is measured at more than one time point; experimental units fall into a one or two class design 2320:
Dinu, I. P.; JD; Mueller, T; Liu, Q; Adewale, AJ; Jhangri, GS; Einecke, G; Famulski, KS; Halloran, P; Yasui, Y. (2007).
521:— same experimental units are measured in the two groups; e.g. samples before and after treatment from the same patients 1364: 395:, which measures the strength of the relationship between gene expression and a response variable. This analysis uses 2631: 1818:
de Souto, Marcilio C. P.; Costa, Ivan G.; de Araujo, Daniel S. A.; Ludermir, Teresa B.; Schliep, Alexander (2008).
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Positive gene set — higher expression of most genes in the gene set correlates with higher values of the phenotype
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Negative gene set — lower expression of most genes in the gene set correlates with higher values of the phenotype
403:. The response variable describes and groups the data based on experimental conditions. In this method, repeated 396: 275: 119:. The median polish algorithm, although robust, behaves differently depending on the number of samples analyzed. 1340: 2072: 374: 2373:"Comparison and evaluation of methods for generating differentially expressed gene lists from microarray data" 1410:"A comparison of normalization methods for high density oligonucleotide array data based on variance and bias" 408: 2625: 2558: 180: 164: 1502:"Comparative analysis of microarray normalization procedures: effects on reverse engineering gene networks" 1147:"Gene set enrichment analysis: A knowledge-based approach for interpreting genome-wide expression profiles" 1086: 411:
assumptions about the distribution of individual genes. This is an advantage over other techniques (e.g.,
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that does not take advantage of these mismatch spots but still must summarize the perfect matches through
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the number of permutations is set by the user when imputing correct values for the data set to run SAM
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Example of an approximately 40,000 probe spotted oligo microarray with enlarged inset to show detail.
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ArrayExplorer - Compare microarray side by side to find the one that best suits your research needs
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Can work with blocked design for when treatments are applied within different batches of arrays
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Clustering is a data mining technique used to group genes having similar expression patterns.
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experiments — DNA microarray with oligo and cDNA primers, SNP arrays, protein arrays, etc.
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of the data. MA plots can be produced using programs and languages such as R and MATLAB.
2278: 1367:; Hobbs, B; Collin, F; Beazer-Barclay, YD; Antonellis, KJ; Scherf, U; Speed, TP (2003). 261:, hierarchical methods and, different distance measures can be found in the literature. 2450: 2423: 2399: 2372: 2348: 2321: 2024: 2000:"Protein Complex-Based Analysis Framework for High-Throughput Data Sets. 6, rs5 (2013)" 1846: 1819: 1792: 1765: 1625: 1600: 1477: 1450: 1317: 1284: 1173: 1146: 366: 324: 241:
K-means clustering is an algorithm for grouping genes or samples based on pattern into
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Data from Oligo or cDNA arrays, SNP array, protein arrays, etc. can be utilized in SAM
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Example of FunRich tool output. Image shows the result of comparing 4 different genes.
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clusters. Hierarchical clustering consists of two separate phases. Initially, a
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List Differentially Expressed Genes (Positively and Negatively Expressed Genes)
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SAM identifies statistically significant genes by carrying out gene specific
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Uses data permutation to estimates False Discovery Rate for multiple testing
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for academic and non-academic users after completion of a registration step.
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Bioinformatics and computational biology solutions using R and Bioconductor
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Estimate the false discovery rate based on expected versus observed values
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Gatto, Laurent; Breckels, Lisa M.; Naake, Thomas; Gibb, Sebastian (2015).
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FARMS - Factor Analysis for Robust Microarray Summarization, an R package
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ArrayMining.net - web-application for online analysis of microarray data
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Reports local false discovery rate (the FDR for genes having a similar d
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containing all the pairwise distances between the genes is calculated.
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Hierarchical clustering is a statistical method for finding relatively
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are used in interpreting the data generated from experiments on DNA (
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are often used as dissimilarity estimates, but other methods, like
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Can adjust threshold determining number of gene called significant
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For each permutation compute the ordered null (unaffected) scores
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Jaskowiak, Pablo A; Campello, Ricardo JGB; Costa, Ivan G (2014).
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IEEE/ACM Transactions on Computational Biology and Bioinformatics
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Plot the ordered test statistic against the expected null scores
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constant is chosen to minimize the coefficient of variation of
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Vinayagam A, Hu Y, Kulkarni M, Roesel C, et al. (2013).
1820:"Clustering cancer gene expression data: a comparative study" 1582: 419:), which assume equal variance and/or independence of genes. 1887: 1543:"A new summarization method for affymetrix probe level data" 1196:
Dr. Leming Shi, National Center for Toxicological Research.
1978: 1285:"Visualization of proteomics data using R and Bioconductor" 2322:"Improving gene set analysis of microarray data by SAM-GS" 1932: 503:— tests whether the mean gene expression differs from zero 133:
Flowchart showing how the MAS5 algorithm by Agilent works.
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GeneChip® Expression Analysis-Data Analysis Fundamentals
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Subramanian A, Tamayo P, Mootha VK, et al. (2005).
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Input Expression Analysis in Microsoft Excel — see below
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expression value below a certain intensity threshold.
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Bolstad BM, Irizarry RA, Astrand M, Speed TP (2003).
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Identification of significant differential expression
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Complete linkage (maximum method, furthest neighbor)
2258:Tusher, V. G.; Tibshirani, R.; et al. (2001). 171:are widely used techniques in microarray analysis. 1264:"LIMMA Library: Linear Models for Microarray Data" 969: 365:are statistically significant. With the advent of 1038:Correlates expression data to clinical parameters 213:Single linkage (minimum method, nearest neighbor) 2594:StatsArray - Online Microarray Analysis Services 1759: 1757: 1755: 1449:Giorgi FM, Bolger AM, Lohse M, Usadel B (2010). 323:responds to a variety of experimental contexts. 2267:Proceedings of the National Academy of Sciences 1500:Lim WK, Wang K, Lefebvre C, Califano A (2007). 592:is equal to the expression levels (x) for gene 2606:FunRich - Perform gene set enrichment analysis 1599:Shi L, Reid LH, Jones WD, et al. (2006). 1541:Hochreiter S, Clevert DA, Obermayer K (2006). 1695:. New York: Springer Science+Business Media. 1219:"GenUs BioSystems - Services - Data Analysis" 989:Order test statistics according to magnitude 469:are calculated based on the number of samples 66:The steps required in a microarray experiment 8: 1813: 1811: 2118:"SAM: Significance Analysis of Microarrays" 1198:"MicroArray Quality Control (MAQC) Project" 314:and curated databases such as Biocarta and 353:, established in 2001 by Virginia Tusher, 347:Significance analysis of microarrays (SAM) 335:Significance analysis of microarrays (SAM) 80:National Center for Toxicological Research 2490: 2449: 2439: 2398: 2388: 2371:Jeffery, I. H.; DG; Culhane, AC. (2006). 2347: 2337: 2296: 2286: 2203: 2023: 1933:"FunRich: Functional Enrichment Analysis" 1845: 1835: 1791: 1781: 1624: 1558: 1517: 1476: 1466: 1425: 1384: 1316: 1172: 1162: 727: 687: 605: 603: 455:SAM is available for download online at 302:. One such method of analysis, known as 26: 2515:"J. Craig Venter Institute -- Software" 2422:Larsson, O. W. C; Timmons, JA. (2005). 2186:Zang, S.; Guo, R.; et al. (2007). 1691:Gentleman, Robert; et al. (2005). 1134: 457:http://www-stat.stanford.edu/~tibs/SAM/ 86:Most microarray manufacturers, such as 2632:Duke data_analysis_fundamentals_manual 1979:"BioCarta - Charting Pathways of Life" 2253: 2251: 2249: 2239: 2237: 2235: 2233: 2231: 2229: 2227: 2225: 2223: 2181: 2179: 2177: 2175: 2173: 2171: 2169: 2167: 2165: 2153: 2151: 2149: 2147: 2145: 2143: 2141: 2139: 2137: 1594: 1592: 361:, for determining whether changes in 7: 2612:Comparative Transcriptomics Analysis 2555:"Ocimum Biosolutions | Genowiz" 1140: 1138: 1113:Significance analysis of microarrays 1062:Error correction and quality control 1041:Correlates expression data with time 985:The SAM algorithm can be stated as: 438:Run SAM as a Microsoft Excel Add-Ins 18:Significance Analysis of Microarrays 1200:. U.S. Food and Drug Administration 1908:"Ariadne Genomics: Pathway Studio" 960: 957: 954: 951: 948: 945: 942: 939: 936: 933: 930: 924: 921: 918: 915: 912: 909: 903: 900: 897: 894: 891: 885: 882: 876: 873: 870: 867: 864: 861: 856: 853: 850: 847: 844: 838: 835: 832: 829: 826: 823: 817: 814: 811: 808: 805: 802: 799: 793: 790: 784: 778: 775: 766: 763: 760: 757: 754: 751: 748: 745: 742: 739: 731: 728: 717: 714: 705: 702: 699: 696: 693: 690: 678: 675: 672: 663: 660: 657: 654: 648: 645: 642: 639: 636: 633: 630: 627: 624: 618: 615: 612: 609: 606: 497:— real-valued (such as heart rate) 399:, since the data may not follow a 25: 2616:Reference Module in Life Sciences 2192:Journal of Biomedical Informatics 596:under y experimental conditions. 82:scientist reviews microarray data 1239:"Agilent | DNA Microarrays" 565: 560: 1427:10.1093/bioinformatics/19.2.185 2535:"Agilent | GeneSpring GX" 1081:available from TIGR, Agilent ( 769: 711: 681: 669: 36:Microarray analysis techniques 1: 2492:10.1093/bioinformatics/bti605 2473:Wilson CL, Miller CJ (2005). 1560:10.1093/bioinformatics/btl033 1519:10.1093/bioinformatics/btm201 1386:10.1093/biostatistics/4.2.249 1051:as that gene) and miss rates 98:Aggregation and normalization 1151:Proc. Natl. Acad. Sci. U.S.A 509:— two sets of measurements 2668: 1783:10.1186/1471-2105-15-S2-S2 234: 178: 2652:Bioinformatics algorithms 2621:SAM download instructions 2205:10.1016/j.jbi.2007.01.002 2016:10.1126/scisignal.2003629 397:non-parametric statistics 384:and computes a statistic 1468:10.1186/1471-2105-11-553 306:Analysis (GSEA), uses a 2441:10.1186/1471-2105-6-129 2390:10.1186/1471-2105-7-359 2339:10.1186/1471-2105-8-242 1837:10.1186/1471-2105-9-497 1164:10.1073/pnas.0506580102 181:Hierarchical clustering 175:Hierarchical clustering 165:Hierarchical clustering 2288:10.1073/pnas.091062498 1301:10.1002/pmic.201400392 1011:Significant gene sets 971: 343: 294: 284:R programming language 199:Spearman's correlation 134: 121:Quantile normalization 83: 67: 32: 2122:tibshirani.su.domains 1076:Background correction 972: 351:statistical technique 342: 292: 195:Pearson's correlation 132: 78: 65: 30: 1245:on December 22, 2007 1108:Microarray databases 1087:Ocimum Bio Solutions 602: 320:transcription factor 42:), RNA, and protein 2279:2001PNAS...98.5116G 1888:"Ingenuity Systems" 1730:10.1109/TCBB.2013.9 472:Block Permutations 401:normal distribution 371:Stanford University 304:Gene Set Enrichment 265:Pattern recognition 2428:BMC Bioinformatics 2377:BMC Bioinformatics 2326:BMC Bioinformatics 1959:"Software - Broad" 1824:BMC Bioinformatics 1770:BMC Bioinformatics 1455:BMC Bioinformatics 967: 344: 308:Kolmogorov-Smirnov 295: 237:k-means clustering 231:K-means clustering 207:Euclidean distance 203:Manhattan distance 169:k-means clustering 135: 84: 68: 40:Gene chip analysis 33: 1702:978-0-387-29362-2 964: 929: 908: 890: 881: 843: 822: 798: 789: 783: 774: 738: 722: 710: 668: 653: 623: 545:Pattern discovery 355:Robert Tibshirani 216:Average linkage ( 16:(Redirected from 2659: 2570: 2569: 2567: 2566: 2557:. 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Retrieved 2559:the original 2549: 2538:. Retrieved 2529: 2518:. Retrieved 2509: 2482: 2478: 2468: 2431: 2427: 2417: 2380: 2376: 2366: 2329: 2325: 2315: 2270: 2266: 2195: 2191: 2125:. Retrieved 2121: 2112: 2101:. Retrieved 2092: 2081:. Retrieved 2077:the original 2067: 2056:. Retrieved 2052:the original 2042: 2007: 2003: 1993: 1982:. Retrieved 1973: 1962:. Retrieved 1953: 1947: 1936:. Retrieved 1927: 1916:. Retrieved 1912:the original 1902: 1891:. Retrieved 1882: 1873: 1864: 1827: 1823: 1773: 1769: 1721: 1717: 1711: 1692: 1686: 1653: 1649: 1643: 1608: 1604: 1577: 1550: 1546: 1536: 1509: 1505: 1495: 1458: 1454: 1444: 1417: 1413: 1403: 1376: 1372: 1365:Irizarry, RA 1359: 1348:. Retrieved 1344: 1335: 1292: 1288: 1278: 1267:. Retrieved 1258: 1247:. Retrieved 1243:the original 1233: 1222:. Retrieved 1213: 1202:. Retrieved 1191: 1154: 1150: 1096: 1079: 1070: 1030:SAM features 984: 980:Fold changes 979: 978: 598: 593: 588: 580: 573: 571: 559: 555: 544: 538: 532: 526: 518: 512: 506: 500: 495:Quantitative 494: 489: 481: 476:recommended; 467:Permutations 405:permutations 392: 385: 379: 346: 345: 296: 280:Bioconductor 268: 242: 240: 226: 184: 162: 148: 136: 125: 113: 101: 85: 57: 54:Introduction 39: 35: 34: 2647:Microarrays 2010:(r5): rs5. 2004:Sci. Signal 1089:(Genowiz). 539:Time course 450:Running SAM 359:Gilbert Chu 187:homogeneous 44:microarrays 2641:Categories 2565:2009-04-02 2540:2008-01-02 2520:2008-01-01 2127:2023-11-24 2103:2008-10-15 2083:2007-12-31 2058:2007-12-31 1984:2007-12-31 1964:2007-12-31 1938:2014-09-09 1918:2007-12-31 1893:2007-12-31 1830:(1): 497. 1350:2023-11-24 1289:Proteomics 1269:2008-01-01 1249:2008-01-02 1224:2008-01-02 1204:2007-12-26 1129:References 1123:Proteomics 1083:GeneSpring 527:Multiclass 442:Controller 430:microarray 417:Bonferroni 409:parametric 300:phenotypes 276:Moksiskaan 159:Clustering 88:Affymetrix 71:Techniques 2608:—software 2602:—software 2596:—software 2590:—software 2048:"DBI Web" 1345:MathWorks 1309:1615-9853 785:# 552:Algorithm 507:Two class 501:One class 375:R-package 329:neoplasms 259:k-medoids 251:k-medoids 2501:16076888 2460:15921534 2409:16872483 2358:17612399 2307:11309499 2214:17317331 2098:"RssGsc" 2034:23443684 1856:19038021 1802:24564555 1738:24334380 1670:17061323 1635:16964229 1569:16473874 1528:17646307 1487:21070630 1436:12538238 1395:12925520 1327:25690415 1183:16199517 1102:See also 533:Survival 513:Unpaired 428:Perform 247:centroid 2451:1173086 2434:: 129. 2400:1544358 2383:: 359. 2349:1931607 2332:: 242. 2275:Bibcode 2073:"SCOPE" 2025:3756668 1847:2632677 1793:4072854 1678:8192240 1626:3272078 1478:2998528 1461:: 553. 1318:4510819 1174:1239896 1085:), and 490:Types: 382:t-tests 312:GenBank 272:GenMAPP 255:k-means 152:t-tests 109:MA plot 92:Agilent 2499:  2458:  2448:  2407:  2397:  2356:  2346:  2305:  2295:  2212:  2032:  2022:  1870:"Home" 1854:  1844:  1800:  1790:  1746:760277 1744:  1736:  1699:  1676:  1668:  1633:  1623:  1567:  1526:  1485:  1475:  1434:  1393:  1325:  1315:  1307:  1181:  1171:  1006:Output 928:  907:  889:  880:  842:  821:  797:  788:  782:  773:  737:  721:  709:  667:  652:  622:  519:Paired 373:in an 167:, and 48:genome 2298:33173 2263:(PDF) 1742:S2CID 1674:S2CID 463:Sizes 413:ANOVA 349:is a 218:UPGMA 2497:PMID 2456:PMID 2405:PMID 2354:PMID 2303:PMID 2210:PMID 2030:PMID 1852:PMID 1798:PMID 1734:PMID 1697:ISBN 1666:PMID 1631:PMID 1565:PMID 1524:PMID 1483:PMID 1432:PMID 1391:PMID 1323:PMID 1305:ISSN 1179:PMID 586:. r 572:The 415:and 357:and 274:and 197:and 90:and 2614:in 2487:doi 2446:PMC 2436:doi 2395:PMC 2385:doi 2344:PMC 2334:doi 2293:PMC 2283:doi 2200:doi 2020:PMC 2012:doi 1842:PMC 1832:doi 1788:PMC 1778:doi 1726:doi 1658:doi 1621:PMC 1613:doi 1555:doi 1514:doi 1473:PMC 1463:doi 1422:doi 1381:doi 1313:PMC 1297:doi 1169:PMC 1159:doi 1155:102 205:or 2643:: 2495:. 2483:21 2481:. 2477:. 2454:. 2444:. 2430:. 2426:. 2403:. 2393:. 2379:. 2375:. 2352:. 2342:. 2328:. 2324:. 2301:. 2291:. 2281:. 2271:98 2269:. 2265:. 2248:^ 2222:^ 2208:. 2196:40 2194:. 2190:. 2164:^ 2136:^ 2120:. 2028:. 2018:. 2006:. 2002:. 1872:. 1850:. 1840:. 1826:. 1822:. 1810:^ 1796:. 1786:. 1774:15 1772:. 1768:. 1754:^ 1740:. 1732:. 1722:10 1720:. 1672:. 1664:. 1654:24 1652:. 1629:. 1619:. 1609:24 1607:. 1603:. 1591:^ 1563:. 1551:22 1549:. 1545:. 1522:. 1510:23 1508:. 1504:. 1481:. 1471:. 1459:11 1457:. 1453:. 1430:. 1418:19 1416:. 1412:. 1389:. 1375:. 1371:. 1343:. 1321:. 1311:. 1303:. 1293:15 1291:. 1287:. 1177:. 1167:. 1153:. 1149:. 1137:^ 725:90 377:. 331:. 257:, 2568:. 2543:. 2523:. 2503:. 2489:: 2462:. 2438:: 2432:6 2411:. 2387:: 2381:7 2360:. 2336:: 2330:8 2309:. 2285:: 2277:: 2216:. 2202:: 2130:. 2106:. 2086:. 2061:. 2036:. 2014:: 2008:6 1987:. 1967:. 1941:. 1921:. 1896:. 1876:. 1858:. 1834:: 1828:9 1804:. 1780:: 1748:. 1728:: 1705:. 1680:. 1660:: 1637:. 1615:: 1585:. 1571:. 1557:: 1530:. 1516:: 1489:. 1465:: 1438:. 1424:: 1397:. 1383:: 1377:4 1353:. 1329:. 1299:: 1272:. 1252:. 1227:. 1207:. 1185:. 1161:: 1049:i 1022:y 1016:y 961:t 958:n 955:a 952:c 949:i 946:f 943:i 940:n 937:g 934:i 931:s 925:d 922:e 919:l 916:l 913:a 910:c 904:s 901:e 898:n 895:e 892:g 886:f 883:o 877:r 874:e 871:b 868:m 865:u 862:N 857:s 854:e 851:n 848:e 845:g 839:d 836:e 833:l 830:l 827:a 824:c 818:y 815:l 812:e 809:s 806:l 803:a 800:f 794:f 791:o 779:f 776:o 770:) 767:e 764:l 761:i 758:t 755:n 752:e 749:c 746:r 743:e 740:p 732:h 729:t 718:r 715:o 712:( 706:n 703:a 700:i 697:d 694:e 691:M 685:= 682:) 679:R 676:D 673:F 670:( 664:e 661:t 658:a 655:r 649:y 646:r 643:e 640:v 637:o 634:c 631:s 628:i 625:d 619:e 616:s 613:l 610:a 607:F 594:i 589:i 583:i 581:d 577:o 574:s 393:j 388:j 386:d 243:K 220:) 20:)

Index

Significance Analysis of Microarrays

microarrays
genome


National Center for Toxicological Research
Affymetrix
Agilent
local regression
MA plot
median polish
Quantile normalization

Factor analysis
t-tests
Hierarchical clustering
k-means clustering
Hierarchical clustering
homogeneous
distance matrix
Pearson's correlation
Spearman's correlation
Manhattan distance
Euclidean distance
UPGMA
k-means clustering
centroid
k-medoids
k-means

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