Full moon, next phase. In given Exercise you found that the expected cell counts failed to satisfy the conditions for inference.
a) Find a sensible way to combine some cells that will make the expected counts acceptable.
b) Test a hypothesis about the full moon and state your conclusion.
Exercise :
Full moon. Some people believe that a full moon elicits unusual behavior in people. The table shows the number of arrests made in a small town during weeks of six full moons and six other randomly selected weeks in the same year. We wonder if there is evidence of a difference in the types of illegal activity that take place.
|
Full Moon |
Not Full |
| Violvent (murder, assult, rape, etc) |
2 |
3 |
| Property (burglary, vandalism, etc) |
17 |
21 |
| Drugs/Alchohol |
27 |
19 |
| Domestic Abuse |
11 |
14 |
| Other OFfenses |
9 |
6 |
a) Will you test goodness-of-fit, homogeneity, or independence?
b) Write appropriate null hypotheses.
c) Find the expected counts for each cell, and explain why the chi-square procedures are not appropriate for this table.