Chapter 6: Statistical Plots 123
7306ENG.DOC Statistical Plots and Analyses Julie Hewlett Revised: 05/29/98 3:52 PM Printed: 05/19/99 9:00 AM
Page 123 of 20
7. Graph and trace the
adjusted Histogram.
*)
" and !(to trace bar
to bar)
Box Plot Box Plot Ö
A Box plot illustrates median applications of a data list. Lines
on the plot, called whiskers, extend from the minimum data
point in the set (minX) to the first quartile median point (Q1)
and from the third quartile median point (Q3) to the maximum
point (maxX). The middle vertical line is the median (Med) of all
the data points.
The first quartile contains all data points between minX and
Med; the third quartile contains all data points between Med
and maxX.
When two Box plots are plotted, the first one plots at the top
of the screen and the second plots in the middle. When three
are plotted, the first one plots at the top, the second in the
middle, and the third at the bottom.
Xmin and Xmax specify minimum and maximum X-axis values
when a Box plot is displayed on the Graph screen. Box plots
ignore Ymin and Ymax values. To adjust Xmin and Xmax
manually, press ' and enter the new values with the
number keys. If you want the calculator to adjust the window
values for you automatically, press ( 7:ZoomStat.
For more information about setting WINDOW values, see
Chapter 9: Function Graphing.
Solution
3 students received a D.
14 students received a C.
7 students received a B.
6 students received an A.
14 scores fall
between 70-80.
Intervals=10
because Xscl=10