Keith and Kirk Are Identical Twins Who Were Separated at Birth

question 202

Multiple Choice

Keith and Kirk are identical twins who were separated at birth and raised in different parts of the country in different environments. When as adults they were reunited, researchers compared them on several psychological characteristics. Compared to identical twins that have been raised together, Keith and Kirk probably have:

• A) as much in common on their psychological characteristics had they been fraternal twins
• B) the same level of similarity from those raised together
• C) even more characteristics in common than if they were raised together
• D) fewer characteristics in common because of different environmental influences

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Definitions:

Population Proportions

The ratio of members in a statistical population that have a particular attribute or characteristic.

Type I Error

A statistical error that occurs when a true null hypothesis is incorrectly rejected.

Type II Error

The error that occurs when a statistical test fails to reject a false null hypothesis, incorrectly concluding that there is no effect or difference when there is.

Null Hypothesis

A default position that there is no association between two measured phenomena or no difference among groups being compared.