Suppose I Am Interested in Knowing Whether Adults Who Are

Multiple Choice

Suppose I am interested in knowing whether adults who are very introverted at age 20 are still highly introverted at age 50. Which of the following statistical analyses will I be most likely to use?

A) a comparison of average introversion scores for a sample of adults aged 20 and another sample aged 50
B) a comparison of average introversion scores at age 20 and age 50 for the same adults assessed longitudinally
C) an analysis of the average amount in introversion between any two measurements of the same people over time
D) a calculation of the correlation between scores on the key variable at two time points in a group of subjects studied longitudinally between age 20 and age 50