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.) Provide an example to illustrate why we should measure the 'order' or 'time' of a measurement.