Pearson vs. Spearman correlation

Correlation measures are commonly used to show how correlated two sets of datasets are. A commonly used measure is the Pearson correlation. To illustrate when not to use a Pearson correlation: If we remove the 2,000 value: Use a non-parametric correlation (e.g. Spearman’s rank) measure if your dataset has outliers. It would probably be best…

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edgeR’s common dispersion

Updated: 2017 September 7th When I was first learning about conducting a differential expression (DE) analysis with RNA-seq data, I found it very difficult to understand the statistical procedures implemented in various R packages that performed the DE analysis. This really bugged me. However, it was not difficult to carry out the analysis, since the…

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The Normal Distribution

Updated 2014 December 19th The normal or Gaussian distribution is commonly occurring continuous probability distribution. The skewness, which is a measure of symmetry (or there lackof), of a normal distribution is zero since the distribution is symmetrical, i.e. it looks the same to the left and right of the centre. Kurtosis can be used to…

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