Reference no: EM132401476
A large mail-order house believes that there is a linear relationship between the weight of the mail it receives and the number of orders to be filled. It would like to investigate the relationship in order to predict the number of orders based on the weight of the mail. From an operational perspective, knowledge of the number of orders will help in the planning of the order-fulfillment process. A sample of 15 mail shipments is selected within a range of 200 to 700 pounds. The results are as follows.
Weight of Mail (Pounds) Orders (In Thousands)
216 6.1
283 9.1
237 7.2
374 11.5
342 10.3
384 10.6
482 14.5
432 13.6
409 12.8
553 16.5
572 17.1
501 15.8
628 19.0
677 19.4
602 19.1
a. Construct a scatter plot.
b. Assuming a linear relationship, use the least-squares method to find the regression coefficients b0 and b1.
c. Interpret the meaning of the slope b1 in this problem.
d. Predict the mean number of orders when the weight of the mail is 500 pounds.
Using the results for above question
a. Determine the coefficient of determination r2 and interpret its meaning.
b. Find the standard error of the estimate.
c. How useful do you think this regression model is for predicting the number of orders?