How does a positive correlation differ from a negative correlation?

A positive correlation indicates a relationship between two variables where they move in the same direction. This means that as one variable increases, the other variable also increases. Conversely, if one variable decreases, the other will also decrease. This type of correlation is essential in research as it helps in understanding how two factors are related; for example, studying the relationship between studying hours and exam scores where an increase in studying hours usually leads to an increase in scores.

The other options provide information that does not correctly describe positive or negative correlations. In a negative correlation, the variables move in opposite directions—when one increases, the other decreases—so options suggesting that both variables either decrease together or increase together, or remain constant do not accurately represent the definitions and characteristics of positive and negative correlations. Therefore, understanding the nature of these relationships is fundamental in research methods in psychology, as it helps in interpreting data and drawing conclusions from research findings.