Question

A​ mail-order catalog business maintains a centralized warehouse for the distribution of products ordered. Management is currently examining the process of distribution from the warehouse and has the business objective of determining the factors that affect warehouse distribution costs. Data that indicate the warehouse distribution costs and the number of orders received over the past 15 months are in the accompanying table. Complete parts​ (a) through​ (f) below.

Month		Cost​ ($thousands)		Orders
1		74.78		4629
2		89.33		5452
3		70.42		4417
4		93.28		5732
5		72.48		4395
6		85.49		5313
7		52.26		3215
8		94.18		5882
9		62.51		3981
10		82.25		5037
11		79.11		4887
12		68.76		4119
13		54.54		3321
14		69.33		4269
15		58.49		3639

a) Assuming a linear​ relationship, use the​ least-squares method to find the regression coefficients b0 and b1. Use the number of orders as the independent variable X and the warehouse distribution costs as the dependent variable Y. b0=_____b1=_____

b) Predict the monthly warehouse distribution costs when the number of orders is 5,500. Yi​(5,500​)=______ thousand ​(Round to two decimal places as​ needed.) (fill in the blank)

d) Compute the​ Durbin-Watson statistic. At the 0.05 level of​ significance, is there evidence of positive auto correlation among the​ residuals? What is the value of the​ Durbin-Watson statistic? D=____ (round to two decimal places as needed)

Use the given table to find the critical values of the​ Durbin-Watson statistic.

dL=___ (round to two decimal places as needed)

dU= ___(round to two decimal places as needed)

Is there evidence of positive auto correlation among the​ residuals?

A.​No, because D>dU.

B.​Yes, because D is between dL and dU.

C.​Yes, because D<d_L.

D. The test in inconclusive

e. Based on the results of​ (c) and​ (d), is there reason to question the validity of the​ model?

There is_____ pattern in the residual plot in​ (c). Part​ (d) provides _______ of autocorrelation.​ Therefore, there is

____________to question the validity of the model. (fill in the blanks)

f. What conclusions can you reach concerning the factors that affect distribution​ costs?

1)As the number of orders​ increases, the distribution costs increase.

2)According to the​ model, the distribution costs are not affected by the number of orders.

3)No conclusions can be reached.

4)As the number of orders​ decreases, the distribution costs increase.

Answer 1