Creating a Probability Histogram
Example: The following data represent the ideal number of children for a
random sample of 900 adult Americans.
x
(number of children)
0
1
2
3
4
5
6
P(x)
.011
.033
.578
.278
.078
.019
.003
Begin by entering the values of the
random variable in list L1 and their
corresponding probabilities in L2.
Remember to enter data into lists go
to
.
Under EDIT select 1:Edit.
Press
.
The cursor is under L1 and ready for
you to enter your data.
Type each number in and after each
entry, press
.
If you need to clear out a list before
you enter data, use the arrow keys
to place the cursor on the name of
the list (L1, L2, etc.).
Then press
clear out the list.
to
Now select the STAT PLOT function
by pressing
This takes you to the STAT PLOTS
menu.
Move the cursor to 1: Plot 1 and
press
You can now set up Plot 1 to do a
probability histogram.
Use the arrow keys to move the
cursor to On and press
Arrow down to Type: and select the
third graph under type (looks like a
histogram-vertical bars).
Press
.
Use the arrow keys to move down to
Xlist: Make sure L1 is here.
If it is not, enter the name of the
correct list. These names are found
above the numeric keys 1-6.
Enter L2 under Freq:
You will need to set up the viewing
window.
Press the
key.
Set Xscl equal to 1.
Look at the values of the random
variable and set Xmin and Xmax
according to those values.
You can set Ymin and Ymax
similarly using the probabilities.
Then press
Dr. JM Raines © 2011