Current technology uses X-rays and lasers for inspection of solder-joint defects on printed circuit boards (PCBs). (Quality Congress Transactions, 1986.) A particular manufacturer of laser-based inspection equipment claims that its product can inspect on average at least 10 solder joints per second when the joints are spaced .1 inch apart. The equipment was tested by a potential buyer on 48 different PCBs. In each case, the equipment was operated for exactly 1 second. The number of solder joints inspected on each run follows:

a. The potential buyer wants to know whether the sample data refute the manufacturer’s claim. Specify the null and alternative hypotheses that the buyer should test.

b. In the context of this exercise, what is a Type I error? A Type II error?

c. Conduct the hypothesis test you described in part a, and interpret the test’s results in the context of this exercise. Use α = .05.

Transcribed Image Text:

PCB 10 9 10 10 11 9 12 8 8 9 10 7 10 11 13 9 10 11 10 12 8 9 9 9 7 12 6 9 10 10 8 7 9 11 12 10 0 10 11 12 9. 7 9 9 10