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1. Data from a study shows that social exclusion causes “real pain”. That is, ac

ID: 3239105 • Letter: 1

Question

1. Data from a study shows that social exclusion causes “real pain”. That is, activity in an area

of the brain that responds to physical pain goes up as distress from social exclusion goes up.

A scatterplot shows a moderately strong linear relationship. Below is regression output from

these data.

a) What is the equation of the least-squares regression line for predicting brain activity

from social distress score?

b) Use the equation to predict brain activity for social distress score of 2.0.

c) What percent of the variation in brain activity among these subjects is explained by

the straight-line relationship with social distress score?

Regression Analysis: Brain versus Distress

The regression equation is Brain = -0.125 + 0.0708 distress

Predictor Coef SEcoef T

Constant -0.1248 0.02465 -5.12

Distress 0.070782 0.009979 6.09

S = 0.0250896 R-Sq = 77.1% R-sq (adj) = 75.1%

l. Data from a study shows that social exclusion causes "real pain". That is, activity in an area of the brain that responds to physical pain goes up as distress from social exclusion goes up A scatter plot shows a moderately strong linear relationship. Below is regression output from these data. a) What is the cquation of the least-squares regression line for predicting brain activity from social distress score? b) Use the equation to predict brain activity for social distress score of 2.0 c) What percent of the variation in brain activity among these subjects is explained by the straight-line relationship with social distress score? Regression Analysis: Brain versus Distress The regression equation is Brain 125 0.0708 distress Predictor Coef SE coef 0.000 -0.1248 Constant 0.02465 -5.12 0.000 0.070782 0.009979 Distress 6.09 S 0.0250896 R-S 77.1% R-sq (adi) 75.1%

Explanation / Answer

a)

The equation of the least-squares regression line for predicting brain activity from social distress score is

Brain = -0.1248 + 0.070782*Distress

b)

Brain = -0.1248 + 0.070782*2 = 0.016764

c)

R-square: 77.1%

The 77.1% of the variation in brain activity among these subjects is explained by the straight-line relationship with social distress score.