Univariate descriptive statistics
The univariate descriptive statistics can be thought of as companions to the univariate descriptive plots. The best way to develop an idea of what the statistics are summarizing or attempting to convey is to always produce a descriptive plot first.
Measures of Central Tendency
Mode
definition: the most frequent class interval
Median
definition: 50th percentile, center point
Mean or Average
definition and properties of the mean
Choosing a measure of central tendency
Measures of Variability or Dispersion
Range
definition: (maximum value - minimum value)
Interquartile range
definition: (75th percentile - 25th percentile) (i.e., width of the box in a boxplot)
Variance and standard deviation
Coefficient of variation
Measures of the shapes of distributions
