13.61 [EX13-61] The company in Exercise 13.60 must also look at other competitive lenses. It obtains another sample of 30 lenses from a lot shipped for comparison. It labeled these lenses as Group 2. Acceptance of this lot also depended on the relationship between the lens power and the optical effect labeled C/O. The sample data (coded in two manners) follow.

Group 2 Power C/O

5.5 0.20

5.5 0.25

••• Remainder of data on Student’s Suite CD-ROM.

Courtesy of Bausch & Lomb

a. Draw a scatter diagram of these data. The xterm is lens power.

b. Calculate the correlation coefficient between the two variables.

c. Test for a significant correlation at the 0.05 level of significance.

d. Find the equation of the line of best fit.

e. Determine whether there is a linear relationship between C/O and lens power for Group 2 by testing the significance of the results (slope of the line of best fit) found in part

d. Use

  0.05.