In exercises that call for two-sample procedures, you may use either of the two approximations for the degrees of freedom that we have discussed: the value given by your software or the smaller of and . Be sure to state clearly which approximation you have used.
7.52 Sadness and spending.
The “misery is not miserly” phenomenon refers to a sad person’s spending judgment going haywire. In a recent study, 31 young adults were given $10 and randomly assigned to either a sad or a neutral group. The participants in the sad group watched a video about the death of a boy’s mentor (from The Champ), and those in the neutral group watched a video on the Great Barrier Reef. After the video, each participant was offered the chance to trade $0.50 increments of the $10 for an insulated water bottle.26 Here are the data:
sadness
| Group | Purchase price ($) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Neutral | 0.00 | 2.00 | 0.00 | 1.00 | 0.50 | 0.00 | 0.50 | ||
| 2.00 | 1.00 | 0.00 | 0.00 | 0.00 | 0.00 | 1.00 | |||
| Sad | 3.00 | 4.00 | 0.50 | 1.00 | 2.50 | 2.00 | 1.50 | 0.00 | 1.00 |
| 1.50 | 1.50 | 2.50 | 4.00 | 3.00 | 3.50 | 1.00 | 3.50 | ||