BIOL 2060 Lecture Notes - Normal Distribution, Data Transformation, Inverse Trigonometric Functions
Document Summary
Normal quantile plot: compares each observation in the sample with its quantile expected from the standard normal distribution. Points should fall roughly along a straight line if the data come from a normal distribution. Shapiro-wilk test: evaluates the goodness of fit of a normal distribution to a set of data randomly sampled from a population. Robust: a statistical procedure is robust if the answer it gives is not sensitive to violations of the assumptions of the method. Data transformation: changes each measurement by the same mathematical formula. Log transformation: most common data transformation, natural ln. Arcsine transformation: only on data that are proportions. Square-root transformation: used when the data are counts. Square transformation: when frequency distribution of the data is skewed left but if it doesn"t work, use the antilog transformation. Reciprocal transformation: when data is skewed right. 13. 4 nonparametric alternatives to one-sample and paired t-tests.
