Let’s revisit Example 4.3

(a) from Chapter 4 and the corresponding hypothesis test, which involved examining the effectiveness of a 15-hour flight instruction safety workshop designed to reduce complacency in flight instruction among CFIs. The hypothetical data set was given in the file Ch_4 Complacency Scores for Hypothesis Testing Example, and we assumed the mean complacency score in the population was μ = 20, which we believed was too high, and we assumed σ = 5. We also noted that complacency was measured using Dunbar’s (2015) instrument where scores could range from 7 to 35, with higher scores reflecting a higher level of complacency in flight instruction. Replicate this example, but now assume that σ is unknown