Question

When faced with a problem or choice, humans can use two different strategies: "cognitive reflectivity," which results in slower responses and few mistakes, or "cognitive impulsivity," which results in quicker responses but also more mistakes. Depending on the individual, these two strategies are used differently. A pilot experiment was conducted on 22 right-handed individuals who were administered a cognitive reflectivity-impulsivity questionnaire, while recording voxel-based morphometry (regional gray matter density) in the ventral medial prefrontal cortex.

Based on the experimental design and the kind of data collected, which statistical test(s) should be used to determine whether there is an association between the cognitive strategy, cognitive reflectivity and the gray matter density of the ventral medial prefrontal cortex? Select all that apply!

		t-test of zero linear correlation
		correlation coefficient (r)
		One-way ANOVA
		z-test
		two sample t-test

Which of the following correctly states the alternate hypothesis?

		Ha: There is no correlation between cognitive reflectivity and gray-matter density
		Ha: There is a correlation between cognitive reflectivity and gray-matter density
		Ha: Gray matter density is independent of cognitive strategies
		Ha: Gray matter density is dependent on cognitive strategies
		Ho: The two groups are equivalent or cannot be distinguished.

Answer 1

Answers:

t-test of zero linear correlation

correlation coefficient (r)

Correct alternative hypothesis:

Ha: There is a correlation between cognitive reflectivity and gray-matter density