Which term describes a relationship where one variable increases as the other decreases?

The term that accurately describes a relationship where one variable increases while the other decreases is known as a negative relationship. In this context, the decrease in one variable corresponds with an increase in another, demonstrating an inverse association between the two. This type of relationship often signifies that the two variables move in opposite directions; as one grows, the other diminishes.

This concept is fundamental in statistical analysis and research methods as understanding the nature of relationships between variables is crucial for predictive modeling, hypothesis testing, and interpreting data accurately. For instance, if we were examining the relationship between gas prices and the quantity of gas purchased, we might expect to find a negative relationship; as gas prices rise, the quantity purchased typically declines.

In contrast, positive relationships or positive correlations indicate that both variables move in the same direction. A null hypothesis, meanwhile, refers to a specific statement that there is no effect or relationship and is often the starting point for statistical testing, so it wouldn't apply in this context of relationship direction.