Question

The table below gives the list price and the number of bids received for five randomly selected items sold through online auctions. Using this data, consider the equation of the regression line, yˆ=b0+b1xy^=b0+b1x, for predicting the number of bids an item will receive based on the list price. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make a prediction if the correlation coefficient is not statistically significant.

Price in Dollars	24	32	33	45	46
Number of Bids	2	3	6	7	9

Table

Copy Data

Step 1 of 6 :  

Find the estimated slope. Round your answer to three decimal places.

Answer 1

Price in dollars (X)	Number of bids (Y)	(X-Xbar)2	(Y-Ybar)2	(X-Xbar)(Y-Ybar)
24	2	144	11.56	40.8
32	3	16	5.76	9.6
33	6	9	0.36	-1.8
45	7	81	2.56	14.4
46	9	100	12.96	36
180	27	350	33.2	99
36	5.4
beta1	0.282857
beta0	-4.78286

Estimated slope = beta 1 = 0.282857

Regression line

y = -4.78286 + 0.282857 (X)

Formula sheet

Price in dollars (X)	Number of bids (Y)	(X-Xbar)2	(Y-Ybar)2	(X-Xbar)(Y-Ybar)
24	2	=(A2-$A$8)^2	=(B2-$B$8)^2	=(A2-$A$8)*(B2-$B$8)
32	3	=(A3-$A$8)^2	=(B3-$B$8)^2	=(A3-$A$8)*(B3-$B$8)
33	6	=(A4-$A$8)^2	=(B4-$B$8)^2	=(A4-$A$8)*(B4-$B$8)
45	7	=(A5-$A$8)^2	=(B5-$B$8)^2	=(A5-$A$8)*(B5-$B$8)
46	9	=(A6-$A$8)^2	=(B6-$B$8)^2	=(A6-$A$8)*(B6-$B$8)
=SUM(A2:A6)	=SUM(B2:B6)	=SUM(C2:C6)	=SUM(D2:D6)	=SUM(E2:E6)
=A7/5	=B7/5
beta1	=E7/C7
beta0	=B8-B9*A8