The variable of interest was the average distance separating traps-called trap spacing-developed by teams of fishermen fishing for the red spiny lobster in St. John's. The trap spacing measurements (in meters) for a sample of 7 teams from A fishing cooperative, 8 teams from B cooperative are listed. For this problem, we are interested in comparing the mean trap spacing measurements of the two fishing cooperatives.

A Cooperative: 93 99 105 94 82 70 86

B Cooperative: 118 94 106 72 90 66 153 98

a) Identify the target parameter for this study. (1)

b) Computer a point estimate of the target parameter. (1)

c) What is the problem with using the normal (z) statistic to find a confidence interval for the target parameter? (1)

d) Find a 90% confidence interval for the target parameter. (2)

e) Use the interval, part d, to make a statement about the difference in mean trap spacing measurements of the two fishing cooperatives. (1)

f) What conditions must be satisfied for the inference, part e, to be valid. (1)