When, from the outset of an experiment, differences exist between the kinds of individuals in one group and those in another group, there is a potential threat to internal validity called
A) contamination.
B) attrition.
C) selection.
D) additive effect of selection and history.
Ans: C) selection.
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Depressed people often elicit negative reactions from people. Therefore, one solution presented in the textbook is to:
A. ask a psychiatrist for an antidepressant B. remind other people that depression can alter one's behavior C. replace negative thoughts with positive thoughts of accomplishment, so that his/her self-esteem increases making him/her more attractive to others D. inform those individuals of the depression
Answer the following statement(s) true (T) or false (F)
The prevalence of bulimia nervosa is lower in developing than in developed countries
Which of the following is true of growth in infancy?
A) Infants grow in spurts. B) Infants grow constantly during the first year of life. C) Growth during prenatal development is less dramatic than growth during infancy. D) The growth rates of taller-than-average infants, as a group, always tend to speed up after the second year of life.
Which of the following is a progressive brain disorder typically associated with old age that leads to a gradual and irreversible decline in cognitive abilities?
A. cyclothymic disorder B. bipolar disorder C. Alzheimer's disease D. Crohn's disease