Stats Ch. 2: Frequency Tables, Frequency Distributions, and Graphic Presentation

cumulative frequency distributions

adding each subsequent frequency to create a total frequency polygon x-axis: variable y-axis (left): frequency y-axis (right): percentage

pie chart

chart that shows the proportion or percentage that each class represents of the total number of frequencies

bar chart

graph that shows qualitative classes on the horizontal axis and the class frequencies on the vertical axis. class frequencies are proportional to the heights of the bars

histogram

graphic presentation of frequency distribution graph in which classes are marked on the horizontal axis and the class frequencies on the vertical axis. class frequencies are represented by heights of bars, bars are drawn adjacent to each other

frequency distribution

grouping of data into mutually exclusive classes showing the number of observations in each class Step 1: decide on number of classes (2^k) Step 2: determine class interval (max-min/k) Step 3: set individual class limits Step 4: tally observations into classes Step 5: count number of items in each class (class frequency) class midpoint: halfway between lower limits of two consecutive classes class interval - subtract consecutive lower limits

frequency table

grouping of qualitative data into mutually exclusive classes showing the number of observations in each class

frequency polygon

shape of distribution, consists of line segments connecting the points formed by the intersections of the class midpoints and the class frequencies