Location Common measures of location, or
central tendency, are the
arithmetic mean,
median,
mode, and
interquartile mean.
Spread Common measures of
statistical dispersion are the
standard deviation,
variance,
range,
interquartile range,
absolute deviation,
mean absolute difference and the
distance standard deviation. Measures that assess spread in comparison to the typical size of data values include the
coefficient of variation. The
Gini coefficient was originally developed to measure income inequality and is equivalent to one of the
L-moments. A simple summary of a dataset is sometimes given by quoting particular
order statistics as approximations to selected
percentiles of a distribution.
Shape Common measures of the shape of a distribution are
skewness or
kurtosis, while alternatives can be based on
L-moments. A different measure is the
distance skewness, for which a value of zero implies central symmetry.
Dependence The common measure of dependence between paired random variables is the
Pearson product-moment correlation coefficient, while a common alternative summary statistic is
Spearman's rank correlation coefficient. A value of zero for the
distance correlation implies independence. ==Human perception of summary statistics==