1. Suppose we find that among couples that have lived together before they marry 60% end in divorce. Further, among couples that did not live together before they marry 45% end in divorce. Identify a variable that subdivides the population into subsets in which it possible that for every subset of the population couples that have lived together before marriage will have a lower divorce rate than their counterparts in that subset. Provide the numbers to make your assertion clear.
2. Explain the circumstances that can lead to a reversal in a comparison between two groups.
3. Provide an example to illustrate why we should measure the 'order' or 'time' of a measurement.
4. Why do we want to measure a predictor of the response and not just a response? Provide an example to illustrate your response.
5. What does the expression "measure all dimensions" mean? Provide an example to illustrate why we need to measure all dimensions.
6. What is meant by ‘an operational definition' of a measure? Why do we need to create such a definition? Provide an example to illustrate an operational definition.
7. How do we know whether all parties to a contract understand the operational definition in the same way?
8. Explain why there is no true value of something we measure.