PLEASE HELP WITH THE QUESTIONS BELOW

8.7) (use a two-sided test assuming equal variances for part b) -- degrees of freedom for the t distribution should be 7.

Applying the Concepts-Basic 8.12 Lobster trap placement. Refer to the Bulletin of Marine Science (April 2010) study of lobster trap placement, TRAPS Exercise 6.29 (p. 324). Recall that the variable of in- terest was the average distance separating traps-calledtrapspacing- deployed by teams of fishermen. The trap- spacing measurements (in meters) for a sample of seven teams from the Bahia Tortugas (BT) fishing cooperative are repeated in the table. In addition, trap-spacing mea- surements for eight teams from the Punta Abreojos (PA) fishing cooperative are listed. For this problem, we are interested in comparing the mean trap-spacing measure. ments of the two fishing cooperatives. BT Cooperative: 93 99 105 94 82 70 86 PA Cooperative: 118 94 106 72 90 66 153 Source: Based on G. G. Sheeler, "Explaining Catch Variation Among Haja California Lobster Fishers Through Spatial Analysis of Trap.Placement Decisions, " Hullcan of Marine Science, Vol. No, No. 2, April 2010 (Table 1). a. Identify the target parameter for this study. b. Compute a point estimate of the target parameter. c. What is the problem with using the normal (z) statistic to find a confidence interval for the target parameter? d. Find a 90% confidence interval for the target parameter. ". Use the interval, part d, to make a statement about the difference in mean trap-spacing measurements of the two fishing cooperatives. f. What conditions must be satisfied for the inference, part e, to be valid?8.13 Last name and acquisition timing. The speed with which consumers decide to purchase a product was investigated in the Journal of Consumer Research (August 2011). The re- searchers theorized that consumers with last names that begin with letters later in the alphabet will tend to acquire items faster than those whose last names begin with letters earlier in the alphabet-called the last name effect. MBA students were offered free tickets to an event for which there was a limited supply of tickets The first letter of the last name of those who responded to an email offer in time to receive the tickets was noted as well as the response time (measured in minutes). The researchers compared the response times for two groups of MBA students: (1) those with last names beginning with one of the first nine letters of the alphabet and (2) those with last names beginning with one of the last nine letters of the alphabet. Summary statistics for the two groups are provided in the table. First 9 Last 9 Lottors: A-l Lottors: R-Z Sample size: 25 25 Mean response time (minutes): 25.08 19.38 Standard deviation (minutes): 10.41 7.12 Source: Based on K. A. Carlson and J. M. Conrad, "The Last Name Effect: How Last Name Influences Acquisition Timing. " Journal of Consumer Research, Vol. 3, No. 2, August 2011. a. Construct a 95% confidence interval for the difference between the true mean response times for MBA stu- dents in the two groups. b. Based on the interval, part a, which group has the shorter mean response time? Does this result support the researchers' last name effect theory? Explain.8.7 Independent random samples from normal populations NW produced the results shown in the next table. LOMAT Sample 1 Sample 2 1.2 4.2 3.1 2.7 1.7 3,6 2.8 3,9 3,0 n. Calculate the pooled estimate of o . h. Do the data provide sufficient evidence to indicate that My > ? Test using a = .10. ( Find a 90% confidence interval for (u- pz). d. Which of the two inferential procedures, the test of hypothesis in part b or the confidence interval in part e. provides more information about ( - #2)