A Researcher Computes the Mean Difference in Locomotion in a Sample

question 75

Multiple Choice

A researcher computes the mean difference in locomotion in a sample of 12 rats before and 30 minutes 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 ( ) ,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)

---

Definitions:

Mass Protest

A large-scale public demonstration or gathering, often expressing opposition to government policies or social injustices, aiming to bring about political or social change.

Student Nonviolent Coordinating Committee

A civil rights organization founded in 1960 that played a central role in the struggle for African American rights through nonviolent protest.

Freedom Summer

A 1964 voter registration drive aimed at increasing the voter registration of African Americans in Mississippi, marked by significant violence and activism.

Voter Registration

The process in which citizens register or enroll to be eligible to vote in elections within their jurisdiction.