Assignment 2

Answers for Assignment 2

1. Quote A. The first quote appears to be a use of subjective probability. The commentator has made a personal judgment that the Premier would make the announcement, but does not attach a number to it, although “probably” implies a large probability (0.7 or more?). There is no way that this probability could be determined by the classical approach since not all the possibilities are known, nor are the outcomes of equal likelihood. Since the Premier was new to the office at the time, there is no prior record of how he made announcements, so there are not data on which to construct a frequency based estimate of the probability.

Quote B. The likelihood appears to be based on the frequency interpretation of probability. The quote makes reference to employees as a whole and those in primary and health occupations. In order to make statements of this type, these employees would have had to be surveyed and the findings cited in the article come from the data provided by the employees. Presumably the sample was large so the frequency approach provides these estimates.

Independence and dependence. The first and second sentences imply dependence of stress on occupation.

P(interpersonal relations a source of stress | primary occupations) = 0.10

P(interpersonal relations a source of stress) = 0.16

P(interpersonal relations a source of stress | health occupations) = 0.21

P(interpersonal relations a source of stress) = 0.16

So the event that interpersonal relations were a source of stress is dependent on being in a primary occupation and is also dependent on being in a health occupation.

The last sentence implies an independence of the events of being in most occupations and the event of feeling stressed at work because of poor interpersonal relations, although numerical values are not provided. The statement that the likelihood does not differ from the average means that the overall likelihood is not changed by being...