1. (4 points) How strongly do physical characteristics of sisters and brothers c

Question

1. (4 points) How strongly do physical characteristics of sisters and brothers correlate? A researcher measue height in inches, x, of the brother and measured the height in inches, y, of the sister for 12 adult sibling pairs. He then computed the least-squares regression line for predicting sister's height from brother's height and found it to be: = 28.037 + 0.521x. a. What does the slope of O.521 tell us? b. By looking at the least-squares regression line, you can see that the correlation between brothers heights and sisters' heights is (choose one): i. Greater than zero ii. Less than zero ii. Unable to be determined without seeing the data and scatterplot According to the regression line, the predicted height of the sister when the brother is 70 inches is: (round to 2 decimal places) c. On his record, one of the brothers that was 70 inches tall had a sister that was 65 inches tall. If the regression line above was used, what is the residual when x is 70 inches? (round to 2 decimal places) d.

Explanation / Answer

Answers to the question below:

1.

a. The slope of .521 says that per increase in brother' height there is .521 inch increase in sister' height

b. Since the slope is greater than 0, i.e. it is .521 we have a positive correaltion. Answer is i. greater than zero
You don't need a scatter plot to check if the relation is positive or negative, just the reg. line equation will do.

2. It will be :28.037+.521*70 = 64.507 inches

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.