Author Question: Explain percentage of variance and give an example. What will be an ideal ... (Read 23 times)

BRWH · **on:** Jun 21, 2018

Explain percentage of variance and give an example.

What will be an ideal response?

Question 2

What were four of Francis Galton's findings from his twin studies?

What will be an ideal response?

Jayson · **Reply #1 on:** Jun 21, 2018

Answer to Question 1

Answer: The percentage of variance refers to the differences among a group of people rather than within one individual. We know that 10 of the variance in human height is determined by environment and 90 by genetics. For this factor, clearly environment is a weak influence while genetics is a strong one. But that does not mean that 90 of any specific person's height is due to genetics. As a child, that specific person may have had poor nutrition or taken a prescription medicine that affected his or her height. Percentage of variance means that among any group of people, 90 of the individual differences in height are due to genetics.

Answer to Question 2

Answer: Galton's findings included: Twins often wore different colors as children so their parents could tell them apart: twins often used their similarity in appearance to pull pranks and then escape punishment by blaming each other; twins' interests and way of speaking were generally similar; and twins seemed to get ill at the same time without catching the illness from each other, suggesting that they had similar constitutions. The twins were not completely alike, however. Galton found that they often sang in different keys and their handwriting was usually distinct.