Question

1. A researcher is interested in determining if there is a difference in the amount of time babies pay attention to other babies and to adults.  The researcher takes a group of 26 babies and randomly assigns them to two groups (there are 13 babies in each group).  In one group, babies watch a video of other babies and in the other group, babies watch a video of adults.  The researcher records how long each baby pays attention to the video.  He finds that babies who watched other babies paid attention for 41 seconds with a standard deviation of 5.2 seconds.  On the other hand, babies who watched adults paid attention for 24.6 seconds with a standard deviation of 8.9 seconds.  At a significance level of .01, is there a difference in how long the babies paid attention to each video?
2. State the null and alternative hypotheses (1 pt).
3. Find the critical value(s) (1/2 pt).
4. Compute the observed value of the test statistic (1 pt).
5. Make a decision to reject or fail to reject the null hypothesis at the specified level of significance (1/2 pt).
6. State your conclusion in terms of the alternative hypothesis (research question) (1 pt).
7. Compute the observed value of the test statistic (1 pt).

Answer 1