Personal Strengths

Question

  Problem 2   Assume that breast cancer affects .8   percent of the female population between 40 and 50 years of age. There are   two kinds of test results: true positive (you have it) and false positive   (the test indicates you do have it, but you really do not). Assume Mammograms   are 90% accurate at spotting people who have breast cancer (true positive),   and are 93% accurate at spotting people who do not (true negative). What are   the false negative and false positive accuracies? If a female tests positive for breast   cancer, compute the likelihood that she indeed has the cancer.    

     Problem 3   A pair of dice is   rolled. The sum of the faces on top is observed. What are the expectation,   variance, and standard deviation of the observed sum?    

Question

A psychologist interested in political behavior measured the square footage of the desks in the official office of four U.S. governors and of four chief executive officers (CEOs) of major U.S. corporations.The figures for the governors were 44, 36, 52, and 40 square feet. The figures for the CEOs were 32, 60, 48, and 36 square feet.

(a) Figure the means and standard deviations for the governors and for the CEOs.

(b) Explain, to a person who has never had a course in statistics, what you have done.

(c) Note the ways in which the means and standard deviations differ,and speculate on the possible meaning of these differences, presuming that they are representative of U.S. governors and large corporations’ CEOs in general.