MATH3330 Section B

Exercise.  October 22, 2001

ID Coffee Stress  Heart  Stress2
1      23    14     6       0
2      35    34     9      47
3      38    58    41       0
4      48    50    31       5
5      52    86    63     166
6      56    73    44      77
7      61    82    69      24
8      62    87    80      50
9      64    74    63      55
10     71    80    72     107
11     74    87    83     115
12     76    92    58      91
13     87   128   113     190
14     97   115    88     132
15    100   123    92     102
16    104   117    92     158
17    107   148   144      84
18    124   146   103     172
19    141   175   145     155
20    154   197   162     229


The above data were artificially produced and represent information from
20 pseudo-subjects on:

Coffee: a measure of average daily caffeine consumption
Stress: a highly reliable measure of stress in the individual's
        work and home
Heart:  an index of heart function (high values mean poor function)
Stress2: an unreliable measure of stress

Your mission is to analyze the relationship between caffeine consumption
and the heart index.  Would this data lead you to believe that caffeine
is bad for you?

Try a variety of models and think about what they mean? Do your results
seem contradictory? Are there explanations to resolve the apparent
contradictions?