Correlations and Considering Explanations

Demonstrating that a correlation exists does not necessarily mean that changes in one variable cause changes in the other variable. A strong correlationmightindicate causality, but there could be other explanations:

For the studies described below, a) decide whether the correlation is positive or negative and b) give one possible alternative explanation for the finding.

Example Problem:

Sarah conducted a study and found that when ice cream sales were low, air conditioner sales tended to be low and that when ice cream sales were high, air conditioner sales tended to be high.

Positive correlation

Alternative explanation: When it is hot, people tend to buy more air conditioners. When it is hot, people tend to buy more ice cream.

1. Researchers investigating the relationship between alcohol and memory found that higher doses of alcohol were associated with increasingly lower scores on a test of memory recall.

1. A college professor notices that the farther students sit toward the back of the room, the worse their grades in the course seem to be.