A Psychologist Conducts Research Using the Twin-Study Method

question 7

Multiple Choice

A psychologist conducts research using the twin-study method. He administers a need for Achievement scale to sets of monozygotic and dizygotic twins and finds a correlation of .50 between the scores for pairs of monozygotic twins. If this study is to demonstrate evidence for a genetic influence on need for Achievement, what would we expect the correlation to be between scores for pairs of dizygotic twins?

• A) Higher than .50
• B) Lower than .50
• C) Very close to .50
• D) There is no way to demonstrate a genetic influence with these data.

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Definitions:

Variable Interval

A reinforcement schedule that rewards a response at random time intervals, without a predictable pattern.

Reinforcement

In behavioral psychology, a process of encouraging or establishing a pattern of behavior by offering reward or punishment.

Quizzes

Short assessments used to measure knowledge, skills, or abilities in a specific area or subject.

Variable Interval

A schedule of reinforcement where a response is rewarded after an unpredictable amount of time has passed, used in operant conditioning to modify behavior.