Which describes a positive declaration in hypothesis testing?

• A. There is no difference between regions
• B. The null hypothesis is true
• C. The data suggest no association between regions
• D. The research hypothesis: the infant mortality rate is higher in one region than another

Answer: (D)

In hypothesis testing, you have a null hypothesis that asserts no difference or no effect, and an alternative hypothesis that asserts there is a difference or an effect. A positive declaration is the alternative hypothesis, the claim researchers are trying to find evidence for.

Saying that the infant mortality rate is higher in one region than another is a directional claim about a difference between groups, which fits the notion of a positive declaration. It explicitly states there is a difference and even specifies the direction of that difference.

The other statements describe a lack of difference, the null hypothesis being true, or no association, which are not positive declarations. They either state no effect or refer to the null rather than making an active claim of a difference.