Q: A study finds that the correlation for a personality trait between identical twins is $$r = 0.60$$ and between fraternal twins is $$r = 0.30. $$What is the estimated heritability of the trait?

$$h^2 = 2$$ \times (0.60 - 0.30) = 0.60$$

Question 1

Which of the following best describes the primary goal of twin studies in personality psychology?

Accepted Answer

To assess the genetic and environmental contributions to personality traits.

Question 2

According to behavioral genetics, which equation best represents the total variance in a personality trait?

Accepted Answer

$$V_P = V_G + V_E$$

Question 3

A researcher finds that identical twins reared apart have more similar personalities than fraternal twins reared together. What does this suggest?

Accepted Answer

Genetic factors play a significant role in personality development.

Question 4

Which of the following is a limitation of adoption studies in determining genetic influence on personality?

Accepted Answer

Adoptive families may not represent the general population.

Question 5

If the heritability estimate for extraversion is $$h^2 = 0.50$, what does this mean?

Accepted Answer

50% of the variation in extraversion in the population is due to genetic differences.

Question 6

Which scenario best illustrates a gene-environment interaction in personality development?

Accepted Answer

A person with a genetic predisposition for anxiety develops anxiety only after experiencing a traumatic event.

Question 7

Which of the following statements about evolutionary psychology and personality is most accurate?

Accepted Answer

Personality traits that increase reproductive success are likely to be passed on.

Question 8

A psychologist is studying the influence of shared environment on personality. Which research design would be most appropriate?

Accepted Answer

Comparing identical twins reared together and apart.

Question 9

Which formula represents the calculation of heritability in behavioral genetics?

Accepted Answer

$$h^2$$ = \frac{V_G}{V_P}$$

Question 10

Which of the following is an example of a nonshared environmental influence on personality?

Accepted Answer

Siblings attending different schools.

Question 11

A study finds that the correlation for a personality trait between identical twins is $$r = 0.60$$ and between fraternal twins is $$r = 0.30. $$What is the estimated heritability of the trait?

Accepted Answer

$$h^2 = 2$$ 	imes (0.60 - 0.30) = 0.60$$

Question 12

Which of the following best explains why personality traits may persist across generations according to evolutionary theory?

Accepted Answer

Traits that enhance survival and reproduction are selected for.

Question 13

Which research method is most effective for separating genetic and environmental influences on personality?

Accepted Answer

Twin studies comparing identical and fraternal twins.

Question 14

If a personality trait has low heritability, what does this imply?

Accepted Answer

Genetic factors have little influence on the trait.

Question 15

Which of the following is NOT a method used to determine genetic influence on personality?

Accepted Answer

Case studies of famous individuals.

Question 16

A psychologist finds that siblings raised in the same family have very different personalities. What is the most likely explanation?

Accepted Answer

Nonshared environmental influences.

Question 17

Which statement best describes the concept of heritability in personality psychology?

Accepted Answer

Heritability refers to the proportion of observed variation in a trait among individuals that can be attributed to genetic factors.

Question 18

Which of the following is a common misconception about heritability?

Accepted Answer

High heritability means a trait is determined only by genes.

Question 19

Which equation would you use to estimate the genetic contribution to a personality trait using twin study correlations?

Accepted Answer

$$h^2 = 2$$ 	imes (r_{MZ} - r_{DZ})$$

Genetics, Evolution, and Personality: Foundations and Influences

Guida di studio - Domande di pratica

Study guide - Flashcard