USING SPLUS TO RUN THE T-TEST FOR EXERCISE 21

If you read in the data (from EX0221.ASC from the datasets from
the Statistical Sleuth link) so it's in a dataframe with weights
in one column and code in the other, so it looks like

weight code
24.5 1
26.9 1
26.9 1
24.3 1
 :   :
24.6 2
27.5 2
31.1 2
28.3 2

You can then use this dataframe in the graphical user interface (gui)
for the t-test.  Hit: statistics>compare samples>two samples>t-test

Check the box that says: Data Has a Grouping Variable
                    Use: weight for Response Variable,
                         code for Grouping Variable
(I needed to recheck the "Data Has a Grouping Variable" box)
Then hit ok.  That seemed to do it for me.

My output was t = -2.2714, pval=.0269 (2 sided), ci (-1.53,-0.10)

Be sure to include a "Summary of Statistical Findings" and
a "Scope of Inference" blurb in this hw solution.  Mimick
what is in the case studies of the previous chapters - it
shouldn't be long.  Remember, interpreting
results is crucial and is something a stat package
will never be able to do (famous last words).