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Consider the following regression based on hypothetical data. We hypothesize tha

ID: 3224006 • Letter: C

Question

Consider the following regression based on hypothetical data. We hypothesize that age, height, and income affect people’s weight. So we run a regression analysis of data from a random sample of 25 people, with weight (in pounds) as the dependent variable and age (x variable 1, in years), height (x variable 2, in inches), and income (x variable 3, in $1,000) as the independent variables. Here is part of the regression output from Excel:

2. With the observation of age=20, height=65, and weight=130, what's the aproximate predicted weight given the regression results? What's the residual?

Coefficients Standard Error t Stat P-value Intercept -44.67264562 50.1927185 -0.890022437 0.383084 X Variable 1 0.738473978 0.239186641 3.08743822 0.005381 X Variable 2 2.367599923 0.799362237 2.96186111 0.007203

Explanation / Answer

The fitted regression model is

weight= -44.67 + 0.74 (age)+ 2.37 (height)

With the observation of age=20, height=65

weight= -44.67 + 0.74 (20)+ 2.37 (65) =124.18

Residual= actual - fitted =130-124.18 = - 5.82