Q1) Large mail-order house believes that there is linear relationship between weight of mail it gets and number of orders to be filled. It would like to investigate relationship to forecast the number of orders, based on weight of the mail. From operational prospective, knowledge of number of orders will help in planning of order fulfilment process. Sample of 25 mail shipments is selected that range from 200 to 700 pounds.
|
Weight of Mail(pounds)
|
Orders (Thousands)
|
|
216
|
6.1
|
|
283
|
9.1
|
|
237
|
7.2
|
|
203
|
7.5
|
|
259
|
6.9
|
|
374
|
11.5
|
|
342
|
10.3
|
|
301
|
9.5
|
|
365
|
9.2
|
|
384
|
10.6
|
|
404
|
12.5
|
|
426
|
12.9
|
|
482
|
14.5
|
|
432
|
13.6
|
|
409
|
12.8
|
|
553
|
16.5
|
|
572
|
17.1
|
|
506
|
15
|
|
528
|
16.2
|
|
501
|
15.8
|
|
628
|
19
|
|
677
|
19.4
|
|
602
|
19.1
|
|
630
|
18
|
|
652
|
20.2
|
i) Create a scattered plot
ii) Suppose a linear relationship, use least-squares method to determine the regression coefficients, b0 and b1
iii) Interpret meaning of the slope, b1, in this problem
iv) Forecast mean number of orders when weight of the mail is 500 pounds
v) Find out the coefficient of determination, r2, and interpret its meaning.