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