A Researcher Computes the Mean Difference in Locomotion in a Sample

question 33

Multiple Choice

A researcher computes the mean difference in locomotion in a sample of 12 rats before and 30 min after an injection of amphetamine.Rats were placed in a box with infrared beams.The number of times rats crossed the beams was used as a measure of locomotion.The mean difference in locomotion was 6.2 ± 8.4 (M_D ± S_D) and this difference was significant.What is the effect size for this result using estimated Cohen's d?

• A) d = 0.74 (medium effect)
• B) d = 1.36 (medium effect)
• C) d = 0.74 (large effect)
• D) d = 1.36 (large effect)

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Definitions:

Charles Darwin

A 19th-century English naturalist, geologist, and biologist best known for his contributions to the science of evolution by natural selection.

Species

A group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding, forming the principal natural taxonomic unit below a genus.

William Graham Sumner

A prominent American sociologist and economist known for his contributions to social Darwinism and conflict theory.

Sociological Topic

A subject or area of study within the field of sociology, focusing on human society, social behavior, and social structures.