Periodically Merrill Lynch customers are asked to evaluate Merrill Lynch¯Financial consultants and services (2000 Merrill Lynch Client Satisfactory Survey). Higher ratings on the client satisfaction survey indicate better service with 7 the maximum service rating. Independent samples of service ratings for two ¯Financial cons
The management of Discount Furniture, a chain of discount furniture stores in the Northeast, designed an incentive plan for salespeople. To evaluate this innovative plan, 12salespeople were selected at random, and their weekly incomes before and after the plan were recorded. Salesperson Before After Sid Mahone $320 $340 Car
Ms. Lisa Monnin is the budget director for Nexus Media, Inc. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample information. Sales ($) 131 135 146 165 136 142 Audit ($) 130 102 129 143 149 120 139 At the .10 significance level, can she conclude t
The null and alternate hypotheses are: A random sample of 15 observations from the first population revealed a sample mean of 350 and a sample standard deviation of 12. A random sample of 17observations from the second population revealed a sample mean of 342 and a sample standard deviation of 15. At the .10 significance
Perform hypothesis testing on one variable's data. (Choose either the intrinsic or extrinsic column.) Perform a t-test by formulating a null and an alternative statement, choosing an acceptable significance value, selecting the test statistic and determining its value from the sample data, comparing the observed value to the cri
If anyone could walk me through the below problem it would be greatly appreciated! Thanks, Brian A magazine is considering the launch of an online edition. The magazine plans to go ahead only if it's convinced that more than 25% of current readers would subscribe. The magazine contacts a simple random sample of 500 curr
National Packing Materials Company claims its X20 box can hold loads up to at least 80 pounds. Smith Widget Company has been using the boxes for one year and feels the boxes fail at lighter loads. Hearing the complaints from Smith, the lead engineer for National Packaging decides to test the company's claim that it can hold at
Two boats, the Prada (Italy) and the Oracle (U.S.A.), are competing for a spot in the upcoming America's Cup race. They race over a part of the course several times. Below are the sample times in minutes. At the .05 significance level, can we conclude that there is a difference in their mean times? Boat Times (minutes) Prad
How does statistics enrich and represent the results of a study? How can statistics be used to misrepresent the results of a study? What is the advantage or disadvantage with using a one-tailed t-test?
T-tests, independent samples, paired and one-way t-tests expalined. When shoud they be used and what kind of data should they be used on?
14. Evolutionary theories often emphasize that humans have adapted to their physical environment. One such theory hypothesizes that people should spontaneously follow a 24-hour cycle of sleeping and waking" even if they are not exposed to the usual pattern of sunlight. To test this notion, eight paid volunteers were placed (indi
Experience raising New Jersey Red chickens revealed the mean weight of the chickens at five months is 4.35 pounds. The weights follow the normal distribution. In an effort to increase their weight, a special additive is added to the chicken feed. The subsequent weights of a sample of five month old chickens were (in pounds):
The amount of money out of income spent on housing is an important component of the cost of living. The total costs of housing for homeowners might include mortgage payments, property taxes, and utility costs (water, heat, electricity). An economist selected a sample of 20 homeowners in New England and then calculated these tota
A personal computer manufacturer is interested in comparing assembly times for two keyboard assembly processes. Process 1 is the standard process used for several years, and Process 2 is an updated process hoped to bring a decrease in assembly time. Assembly times can vary considerably from worker to worker, and the company deci
A shipment of crankshafts is believed to be defective. A simple random sample of 16 is drawn from a large shipment. Check to see if the sample is any different from the assumed population mean of 224. 224.12 223.960 224.098 224.001 224.089 224.057 224.017 223.987 223.913 223.982 223.976 223.999 223.989 223.902 2
#5 In an investigation of the possible brain damage due to alcoholism, CAT scans were used to measure brain densities in eleven chronic alcoholics. Each alcoholic was paired with a non-alcoholic control selected to match the alcoholic on age, gender, education and other factors. The brain densities are given in the table. Pa
1. Dunkin Donuts advertises that a dozen of their donuts weighs about 43 oz. A certain baker has figured out that she can stay out of trouble with her manager if each donut weighs about 3.6 oz. To test her donut-making process, she randomly selects thirty-one donuts after baking and weighs them. The average of the sample
2). Sociologists Bellas, Ritchey and Parmer (2001)16 conducted an analysis of the greater gap in faculty salaries. Data consistently indicate how women faculty members earn less than their male counterparts. Differences have been attributed to individual difference, as well as employer and institutional discrimination. For their
As a researcher I would like to evaluate the effectiveness of the workout programs purchased. This done by comparing the weight loss for a sample size of n=1 person who uses the bean workout program for a period of 5 days a week, and for a sample size of n=1 who uses the x90u workout program for a period of 3 days a week. At t
1. What factor determines whether you should use a z-score or a t statistic for a hypothesis test? 2. Several factors influence the value obtained for a t statistic. Some factors affect the numerator of the t statistic and others influence the size of the estimated standard error in the denominator. For each of the following
The average electric bill for residents of Anderson creek is at least 52.98 per month. Develop the appropriate null and alternative hypothesis. What is the type I error in this situation? What is the type II error in this situation? Full time PhD students receive an average salary of 12, 837 according to the US Department of
See the attached file. The average annual rent for office space in Tampa was 17.63 per square foot. A real estate agent selected a random sample of 15 rental properties and found that the mean rent was 18.72 per square foot, and the standard deviation was 3.64. At ?=.05, test the clan that there was no difference in the rents.
Aishka is 67-inch-tall, and she weighs 135 lbs. If the medium height of Puerto Rican women has a normal distribution with µ = 65 inch tall with standard deviation of 2.5 inches, and the weight of the women has a normal distribution µ = 125 lbs with a standard deviation of 10 lbs. Determine what is the most usual and common cha
A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Though the two brands have been comparable in the past, some technological advances were recently made in the Brand 1 manufacturing process, and the consumer group is testing to see if Brand 1 will outperform Brand 2. Tread wear c
86 total students were asked: Do you feel sleep deprived? Mean # hours of sleep Yes (51 students) 5.94 No (35 students) 7.06 Ho: mean = 7 hours of sleep, no feeling of sleep deprivation Ha: mean = < 7 hours of sleep, feeling of sleep deprivation Ple
An investigator wants to assess whether the mean m = the average weight of passengers flying on small planes exceeds the FAA guideline of average total weight of 185 pounds (passenger weight including shoes, clothes, and carry-on). Suppose that a random sample of 51 passengers showed an average total weight of 200 pounds with a
A consumer electronics firm has developed a new type of remote control button that is designed to operate before becoming intermittent. A random sample of 25 of new buttons resulted in a mean of 1,241.2 hours of continuous service with a standard deviation of 110.8 hours. The current best remote control button in the market ha
1. A sample of 64 observations is selected from a normal population. The sample mean is 215, and the sample deviation is 15. Conduct the following test of hypothesis using the .03 significance level. Ho: µ ≥ 220 H1: µ<220 a. Is this a one or two tail test? b. What is the decision rule? c. What is the value of the
1. Mary claims to be able to hypnotically cause her clients to perform significantly higher on the SAT. The national mean is 1200 with a standard deviation of 100. Under strictly controlled testing, a random sample of 200 of her clients revealed a mean score of 1210. Does this data support her claim. Show all steps. 2. The
A furniture store claims that a specially ordered product will take, on average, M = 35 days (5 weeks) to arrive. The standard deviation of these waiting times is 8 days. We suspect that the special orders are taking longer than this. To test this suspicion, we track a random sample of 100 special orders and find that the orders