Question

WUJIUNTICI Suppose Coach Theil wants to measure the performance of all the track athletes. He wants to specially track the effect of their diet (Diet, measured in grams or g) on their field performance (Performance, measured in meters per second or m/s). Other coaches also include intensity of the field training Training) and sufficient (Rest) as parameters while evaluating athletes performances. If Po denotes the intercept of the population regression line and Mother denotes the error term, which of the following equations describes the regression Coach Theil wants to run? O A. Diet= Bo + BPerformance Performance + Mother OB. Diet = Bo + Brest Performance + Mother- OC. Performance = Bo + B Training Training + Mother- OD. Performance = Bo + B Diet Diet + Mother- The variables explicitly excluded from Coach Theil's population regression line are incorporated in Which of the following statements are true in describing the coefficients of the regression line when Bo = 6.2 m/s? (Check all that apply.) O A. For a given diet X, the intercept shows the predicted value of performance of the athletes when the diet is zero. As a zero diet is improbable, the value of the intercept would have no real-world meaning in this case. B. The slope, Boiet, is the change in performance due to a unit change in the diet. C. The slope, Boiet, is the percentage change in performance due to a unit change in the diet. D. For a given diet X, the intercept shows the predicted value of performance of the athletes when the diet is zero. So, the value of intercept has a significant real-world relevance as it highlights the athletes' performance without a diet. Suppose the slope of the regression line is 0.12 and no other factors affect athletes' performance apart from their diet. If the athletes' performance improved by 3.90 m/s within a month, the change in their diet in this month would have been g. (Round your answer to one decimal place.)

Answer 1

Dependent variable = performance. Independent variable - Diet. Intercept = Bo error term = Lother ut foret to the be the coefficient attached the independent variable ive Diet. 1 Hence our regression equation will be, I Performance = Pot Piet & Diet & Mother So the correct answer is option (o). → The error term Mother measures the impact of other variables which can impact the performance for eg the variable Rest can also affect the performance of athelete but it is not included in the above regression equation. Hence the impact of Rest on performance is accounted for oy the variable lorner .. The variable explicitly excluded from Coach

classmate > y = lot B.X tu li yPerformance, X - Diet. ELY) = Bo + Bx E(X) + Eltothen) = ELY) - Bo + Bx E (x) I so when x=0, then Ely) = ßo + B2 -0 = ße Thus ßo shows the value (expected] of performance when X (Diet) is zero. But since zero diet is improbable the given value of ßo i.e Bo = 6.2 m/s has n é real world meaning So correct answer is option (A). 3 we have, - y = dy Bot Box + Mother 0 + Bx to dy is slope of regression line.

Гtula axe фиолун By = 0.12 dy = 3.90 dx = ? So using dy. By dx = 7 dx = 3.90 0.12 > dx = 32.5 so the change in their died in this month world have been 32-579