Reference no: EM131137859

1.) Sixty-four students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Research question: At α = .01, is the degree of certainty independent of credits earned?
This question requires data regarding the answers of the two questions asked to the 64 students.

2.) A student team examined parked cars in four different suburban shopping malls. One hundred vehicles were examined in each location. Research question: At α = .05, does vehicle type vary by mall location? (Data are from a project by MBA students Steve Bennett, Alicia Morais, Steve Olson, and Greg Corda.)
This question requires the data collected by the student team.

3.) High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as "Low" (under 88 decibels), "Medium" (88 to 91 decibels), or "High" (92 decibels or more). There are three flight phases (Climb, Cruise, Descent). Research question: At α = .05, is the cockpit noise level independent of flight phase?
This question requires data collected by the co-pilot.

4.) Can people really identify their favorite brand of cola? Volunteers tasted Coca-Cola Classic, Pepsi, Diet Coke, and Diet Pepsi, with the results shown below. Research question: At α = .05, is the correctness of the prediction different for the two types of cola drinkers? Could you identify your favorite brand in this kind of test? Since it is a 2 × 2 table, try also a two-tailed two-sample z test for π1 = π2 (see Chapter 10) and verify that z2 is the same as your chi-square statistic.Which test do you prefer? Why?
This question requires the data collected.

5.) Johnson's Service Center has devised three potential options available to preferred customers who redeem coupons and buy at least 10 gallons of fuel when they stop in. Option A is a flat 3 cents off each gallon. Option B is a combination of 2 cents off plus another $1 discount on the regular price of a $5 deluxe car wash. Option C is a $2 discount on the same $5 deluxe car wash but no reduction in the fuel purchase. The owner, Harold Johnson, ran each option on three different two-week trial periods and tracked daily sales receipts from those customers who redeemed their coupons. Results are shown in the table below:

Option A	Option B	Option C
$453 507 513 521 511 615 601 552 551 505 515 512 476 427	$492 514 536 511 528 678 611 653 596 516 534 543 498 437	$467 525 516 500 435 462 411 674 512 559 624 711 512 416

State the null and alternate hypotheses to test for equal population means. (50%)
Let μ_1,μ_(2,) ? μ?_3 respectively denote the mean sales receipts of the three options.
Null hypothesis H0: μ_1=μ_2=μ_3 (the mean sales receipts of the three options are equal)
Alternative hypothesis μ_1,μ_(2,) ? μ?_3 are not all equal.( the at least one of the three population mean total returns is different from the others)

b) (50%) Below are the results from EXCEL of ANOVA of the data at the 0.05 level of significance. Do the sample data indicate the at least one of the three population mean total returns is different from the others? Why? (Explain using "F" and "Fcrit")

Anova: Single Factor
SUMMARY
Groups	Count	Sum	Average	Variance
Column 1	14	7259	518.5	2555.962
Column 2	14	7647	546.2143	4340.335
Column 3	14	7324	523.1429	8389.209
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
Between Groups	6169	2	3084.5	0.605377	0.550917	3.2381
Within Groups	198711.6	39	5095.168
Total	204880.6	41