STA 2023 Lecture Notes - Lecture 10: Interquartile Range, Unimodality, Standard Deviation
Document Summary
The distribution of a quantitative variable slices up all the possible values of the variable into equal width bins and gives the number of values falling into each bin. A histogram uses adjacent bars to show the distribution of a quantitative variable. Each bar represents the frequency of values falling in. A region of the distribution where there are no values. A stem and leaf display shows quantitative data values in a way that sketches the distribution of the data. Dotplot a dot plot graphs a dot for each case against a single axis. The measures of center are mean and median. A numerical summary of how tightly the values are clustered around the center. Measures of spread include the iqr and standard deviation. A hump or local high point in the shape of a distribution of a variable. The apparent location of modes can change as the scale of a histogram is changed.
