You conduct a study on a group of individuals to examine the role of exercise on depression alleviation. You assign the first 50 people who are motivated to sign up to the experimental group, and the second group of 50 people, who sign up much later, to the control group. After one month, you find that the experimental group (who exercised three times a week on average) is significantly less depressed than the control group (who exercised one time a week on average). Although you may be tempted to conclude that exercise helps stave off depression, you cannot because of a lack of _____ in your study.
Answer: random assignment
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If a workgroup operates under the ________________ norm, then each person in the group will be rewarded in direct proportion to the amount that he or she contributed
Fill in the blank(s) with correct word
Sleep-deprived people act like intoxicated people in terms of judgment, attention, and reaction time.
Answer the following statement true (T) or false (F)
Based on the relationship between perception and the physical properties of light, you should infer that if the human nervous system were not wired to respond to differences in the wavelengths of reflected light, people would not be able to:
a. detect differences in brightness b. respond accurately to movement c. detect differences in colors d. have full peripheral vision
At which age does myelination proceed the most rapidly?
A. during the prenatal time period B. the first three months of life C. from birth to age 4 D. from age 4 to age 8