AP Statistics 1.2 - Displaying Quantitative Data with Graphs

dotplot

shows each data value as a dot above its location on a number line.

roughly symmetric

if the right side of the graph (containing the half of observations with the largest values) is approximately a mirror image of the left side.

skewed to the right

if the right side of the graph is much longer than the left side.

skewed to the left

if the left side of the graph is much longer than the right side.

overall pattern of a distribution

center (median), shape (skewed/symmetric), spread (variabiltiy/range), outliers

stemplot

shows each data value separated into two parts: a stem, which consists of all but the final digit, and a leaf, the final digit. The stems are ordered from lowest to highest and arranged in a vertical column. The leaves are arranged in increasing order out from the appropriate stems.

histogram

shows each interval of values as a bar. The heights of the bars show the frequencies or relative frequencies of values in each interval.