Question

please answer this economics question completely..thank you its urgent.

a. III- (5pts) In an econometrics course, the relationship between the expected score earned by students s related to the time in minutes) spent taking it, according to the following model: E(Score/Time) = 49+0.24Time What is the estimated effect of an additional 10 minutes on a student's score? b. Find the expected Score for a student who is given 120 minutes to complete the exam. (1pt) c. If the student in a. receives a score of 90, calculate the residual. (1pt) d. If the average time allocated to all students for the test is 140 minutes, what is the estimated average -core? e. If the time allocated to a student to take the test is 140 minutes, does this mean he/she will receive he same score found in d.? Explain. (1pt) IV- 6pts) Consider the following joint distribution of two random variables X and Y: Y\X 1 2 Total 1 0.11 ? ? 2 ? 0.52 ? Total ? 0.68 ? a. Calculate E(Y) and V(Y) (2pts) b. Find the conditional probability of X given Y=2 (1pt) C. Calculate E(X/Y=2) and V(X/Y=2) (2 pts) d. Are the variables statistically X and Y independent? (1pt)

Answer 1

##According to Chegg policy it is not possible to answer multiple questions -Questions with sub questions are fine.

a) Change in estimated score = change in time* slope

Change in estimated score= (10)0.24 = 2.4

So when time given increases by 10 minutes ,the score would increase by 2.4 points

b) We have the regression function

E(score) = 49+0.24*time

Putting time = 120 minutes

E(score) = 49+0.24(120)= 77.8 points

c) Actual score is 90

Estimated score is E(score)= 49+0.24*time

Residual = Actual - predicted

Residual= 90-49-0.24*time = 41-0.24*time

d) E(score )= 49+0.24*(140)

E(average score) = 82.6

e) In part d we are given the average score and time , the score varies from student to student , but the average is 140