A health magazine recently reported a study in which researchers claimed that iron supplements increased memory and problem-solving abilities in a random sample of college women. All of the women took memory and problem-solving tests at the beginning of the study, then took iron supplements, and then took the same tests again at the end of the study. What is wrong with this design? What confounds
could be leading to the results of improved memory and problem-solving skills?
What will be an ideal response?
This is a single-group pretest/posttest design. In other words, there is no control group, and there should be a control group. The problem is that the subjects could have done any number of things between the pretest and posttest (in addition to taking iron supplements) that could have also led to this improvement. Thus, there could be a practice effect or a maturation effect.
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Consider the following sentences: "Captain Ahab wanted to kill the whale. He cursed at it." These two sentences taken together provide an example of a(n)
A. instrument inference. B. garden path sequence. C. global connection. D. anaphoric inference.
Venessa's hand is more proximal to her body than her shoulder.
Answer the following statement true (T) or false (F)
Source credibility has an impact on attitudes when:
a. the message is presented in oral but not written form b. the audience is made aware of the credibility of the source before the message is delivered c. the audience is made aware of the source credibility immediately after the message is delivered d. the audience is unusually persuasible e. the audience is unusually resistant to persuasion
Helmholtz's explanation of color vision is called the __________
a) opponent-process theory. b) additive color mixing theory. c) trichromatic theory. d) reductive color mixing theory.