Question

Subjects in the weapon condition were only slightly, but not significantly, less accurate than controls on the 20-item questionnaire. Weapon present subjects were correct on 45.8% of the items, while control (weapon absent) subjects were correct on 50.3% of the items, t(34) = 1.37, p > .05, one tailed.

1. What kind of study design is this (experimental or correlational)

2. If experimental what is the independent and dependent variable

3. What kind of statistical test did the author run, and how do you know the used this test?

4. What do you think the null and alternative hypothesis are in this study? You might have to guess, but make it an educated guesses!

Answer 1

1. This is an experimental study. This is indicated by the fact that the study uses control groups, which is a characteristic feature of experiments.

2. The independent variable is weapon presence while the dependent variable is accuracy.

3.The authors have run a t test. This can be ascertained due to the fact that differences between two groups of the study are being assessed. Also the results are indicating the value of the t statistic

5. The null hypothesis is: Weapon presence has no significant impact on accuracy.

The alternative hypothesis is: Weapon presence has a significant impact on accuracy.