Check your understanding of correlation by interpreting the meaning of the correlation in item 1 and by guessing the direction (positive or negative) of the correlations in item 2.
1. Researchers have found a substantial positive correlation between youngsters’ self-esteem and their academic achievement (measured by grades in school). Which of the following are acceptable conclusions based on this correlation?
a. Low grades cause low self-esteem.
b. There is an association between self-esteem and academic achievement.
c. High self-esteem causes high academic achievement.
d. High ability causes both high self-esteem and high academic achievement.
e. Youngsters who score low in self-esteem tend to get low grades, and those
who score high in self-esteem tend to get high grades.
2. Indicate whether you would expect the following correlations to be positive or negative. Explain why you think the way you do.
a. The correlation between age and visual acuity (among adults).
b. The correlation between years of education and income.
c. The correlation between shyness and the number of friends one has.