Chapter 6.C, Problem 51E

Normal Distributions in StatCrunch. Go to the work space and generate approximate data for a normal distribution by choosing “Data” and then “Simulate” and “Normal.” You can generate 100 data values by entering 100 for “Rows” and 1 for “Columns.” Then enter values for the mean (choose 0) and standard deviation (choose 3).

a. Once the data values are displayed, make a bar graph of them showing relative frequency. A window will appear to ask if you want the data binned first. Respond “OK.” Comment on the shape of the distribution.

b. You will get a better picture of the distribution if you bin the data manually. Go to “Data” and “Bine” and then enter -4 for “Start at” and 0.5 for “Binwidth.” A new column of binned data appears in the work space. Make a bar graph of the binned data.

c. Repeat parts (a) and (b) with fewer than and more than 100 data values. Comment on how well the resulting data sets approximate a normal distribution.