Nonparametric statistical test approaches in genetics data

RAKESH Kumar Saroj, Dr.K.H.H.V.S.S. Narsimha Murthy, Mukesh Kumar

Abstract


The biggest challenge of genetic research lies in significant and intellectual analysis of the large and complex data sets generated by the cutting edge techniques like massively parallel DNA sequencing and genome wide analysis. Statistical analyses are the most important of such experimental data. When the data are not normally distributed and using non numerical (rank, categorical) data then use the nonparametric test for exact result of research hypothesis. Order statistics are among the most fundamental tools in non-parametric statistics and inference. Non parametric test does not depend upon parameters of the population from which the samples are drawn, no strict assumption about the distribution of the population.
Nonparametric tests are known as distribution free test also because their assumptions are less and weaker than those connected with parametric test. Nonparametric test does not follow probability distribution. To analyze microarrays and genomics data several non-parametric statistical techniques are used like Wilcoxon’s signed rank test (pre-post group),Mann-Whitney U test (two groups) or Kruskal-Wallis test (two or more groups).Importance of this paper is to look at the nonparametric test how to use in genetic research and provide the understanding of these test.

Keywords


Nonparametric test, Wilcoxon’s signed rank test, Mann-Whitney test, Kruskal-Wallis test

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References


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