In a Study of the Effectiveness of a Treatment for Depression,a

question 28

Multiple Choice

In a study of the effectiveness of a treatment for depression,a psychologist assesses patients' symptoms of depression using a reliable questionnaire both before and for several months after treatment.During the same time period,the psychologist also assesses the symptoms of individuals who are randomly assigned to a waiting-list control group.The results indicate that individuals in both groups experienced a decrease in their symptoms over the 8-month time period of the study.One threat to internal validity the researcher should consider is

• A)regression.
• B)maturation.
• C)selection.
• D)all of these

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Definitions:

Compounded Quarterly

The process of calculating interest on both the initial principal and the accumulated interest from previous periods on a quarterly basis.

Amortization Period

The total length of time over which equal regular payments will repay a loan.

Equal Payments

Regular payments of the same amount over the term of a loan or mortgage.

Compounded Semi-Annually

The process wherein the interest earned on an investment is added to the principal balance twice a year, resulting in compound growth.