[EX06-134] A large sample was randomly selected from a competitive product and evaluated for a particular lens dimension. It was then compared with its specification range of Nominal

(0.000)  0.030 unit. A total of 110 lenses were evaluated. The data were coded in two ways and shown here:

0.020 0.043 0.002 0.002 0.018

0.016 0.051 0.024 0.024 0.032

••• Remainder of data on Student’s Suite CD-ROM Source: Courtesy of Bausch & Lomb (Variable not named and data coded at B&L’s request.)

a. Calculate the mean and standard deviation of the data.

b. Create a histogram and comment on the pattern of variability of the data.

c. Use tests for normality and/or the empirical rule as confirmation of the normal appearance. Explain your findings.

d. Determine the observed percentage of conformance to specification. That is, what percentage of the measurements did fall within the specification range of 0.000  0.030 unit?