The figure for this exercise is a scatterplot of average math test score versus
ID: 3315390 • Letter: T
Question
The figure for this exercise is a scatterplot of average math test score versus percent of graduating seniors who took the test for the 50 states. The regression line for these data is expressed with the following formula 575 550 525 500 475 10 20 30 80 Percent taking test Average math = 575-1.11 (Percent took) A) From the choices below, the best interpretation of the slope estimator is: For each 1-percent decrease in the percentage of high school graduates taking the test, the average math test score decreases 1.11 points If all high school seniors in a particular state take the exam, the average math score is expected to be 575 points If no high school seniors in a particular state take the exam, the average math score is expected to be 575 points For each 1-percent increase in the percentage of high school graduates taking the test, the average math test decreases 1.11 points For each 1.11 point decrease in average math test scores, the percentage of high school graduates taking the test increases by 1% B) In a certain state, only 6% of graduates take the test. What is the predicted average math test score for this state? (Round the answer to two decimal places.) C) Suppose that the average math test score was 578 for the state in part (b). What is the residual (prediction error) for this state? (Round the answer to to two decimal places.)Explanation / Answer
a)3rd option
for each 1-percent increase in the prencentage f high school graduates tajking the test ; the average math test decreases 1.11 points
b) estimated test score =575-1.11*6=568.34
c)
residual =actual-predcited =578-568.34=9.66