Case study

Complete the following steps for given cases

  1. Determine the appropriate method
  2. Define hypothesis test
  3. Use SAS to carry out the test and justify all assumptions
  4. State the conclusion

Case 1

Biologists were interested in the distribution of trees in a wooded area. They intended to use the number of trees per 100-square meter plot as their unit of measurement. However, they were concerned that the shapes of the plots might affect the number of trees in the plot. They counted the numbers of trees in square plots, round plots, and rectangular plots. The data is available at treeshape.csv. The question is to test the impact of shapes on the number of trees.

Case 2

Researchers conducted a randomized, doubl-blind, clinical trial in which some patients with schizophrenia were given the drug clozapine and others were given haloperidol. After one year, 61 of 163 patients in the clozapine group showed clinically important improvement in symtoms; compared with 51 out of 159 in the haloperidol group. The question is to compare the drug clozapine and haloperidol.

Case 3

A sample of 15 patients was randomly split into two groups as part of a double-blind experiment to compare two pain relievers. The 7 patients in the first group were given Demerol; the other 8 patients in the second group were given an experimental drug. They report numbers of hours of pain relief is in relief.csv. Is Demerol different than the experimental drug on the effects?

Case 4

A researcher was interested in the relationship between forearm length and body height. He measured the forearm lengths and heights of a sample of 16 women and obtained data in forearm.csv. Is forearm length affected by body height?