Basic Statistics

obtained by plotting the time in which a variable is measured on the horizontal axis and the corresponding value of the variable on the vertical axis. Line segments are then drawn connecting the points. 

constructed by drawing rectangles for each class of data. The height of each rectangle is the frequency or relative frequency of the class. The width of each rectangle is the same and the rectangles touch each other. 

categories into which data are grouped

smallest value witin the class

largest value within the class

1. Decide number of classes. Should be between 5-20 classes. Smaller the data set, fewer classes you should have

2. Compute class width

          Largest data value- smallest Data Value/ # of classes.

         Round value up to convenient number

Step1: Stem of a data value will consist of the digits to the left of the right most digit. The leaf of a data value will be the rightmost digit

Step 2: Write the stems in a vertical column in increasing order. Draw a vertical line to the right of the stems

Step 3: Write each leaf corresponding to the stems to the rigt of the vertcal line

Step 4: Within each stems, rearrange the leaves in ascending order, title the plot, and include a legend to indicate what the values represent.