A forester is interested in determining which treatment is more effective at combating a particular insect infestation. The three treatments in question are: 1) cut down all visibly infected trees (CUT), 2) treat visibly infected trees with newly developed pesticide (TREAT), or 3) do nothing (CONTROL). A random selection of wooded areas is obtained where the infestation is present. Each forest is randomly assigned to one of the three aforementioned treatments. The forests are monitored for a period of 12 years after the initial treatment is applied. The number of forests that are classified as "infected" is recorded for each forest in three-year increments.
Treatment
Subsequent Infestations Cut Control Treat Total
0 175 181 187 543
1 36 33 24 93
2 2 7 1 10
3 1 1 0 2
4 0 2 0 2
Total 214 224 212 650
Among trees treated with the newly developed pesticide (TREAT), what proportion of trees had 0 subsequent infestations? Hint: This is a conditional proportion from the conditional distribution of subsequent infestations for trees treated with the pesticide (TREAT).
options:
a. 0.288
b. 0.882
c. 0.344
d. 0.187