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Hypothesis Testing

Statistical Techniques in Business & Economics

The mean rate of return on portfolio A (12 stocks) was calculated to be 11% with a standard deviation of 3.4%; the mean rate of return on portfolio b (10 stocks) was determined to be 12.8% with a standard deviation of 4%. At the .05 significance level,: a. F = 3.02, we can conclude that there is more variation in portfolio

To test whether a server can average more than $20 per day.

At the time he was hired as a server at the Family Restaurant, Bob was told, "You can average more than $20 a day in tips." Over the first 36 days he was employed at the restaurant, the mean daily amount of his tips was $24.85 with a standard deviation of $3.24. With a 1% (or .01) Level of Significance, can Bob conclude that he

To test if learning the techniques improves the score

Advertisiments claims that learning a technique will improve the test scores for students The scores of the ten randomly selected students are recorded before and after the technique. For each randomly selected sample, assume the distribution of the population is norma,=l. At a=0.10 is there enough evidence to conclude tha

Critical Values of t and Z

Basically trying to figure out once you get the test statistics how you determine critical value through the Table chart. Trying to find critical value for test statistics of 2.36 with 10 subjects, 7 had higher scores, 2 had lower scores, and 1 score did not change. Using the traditional method of hypothesis testing. Use a

EFFECTIVE COMMUNICATION TECHNIQUES

Details: Piggybank has narrowed its options down to two incentive plans: A. cash back when the consumer makes an online purchase; and B. cash back when the consumer makes a purchase at a clothing store. the bank doesn't know whether consumers would shop online more than at clothing stores. Information experts has placed you

A department store accepts three types of credit cards

A department store accepts three types of credit cards: MC, Visa and their own. The sales management is interested in finding out whether there is a difference in the mean amounts charged by the customers on the 3 cards. A random sample of 18 credit card purchases (rounded) revealed the following amounts. At the 0.05 signific

Arithmetic and geometric mean annual growth rate

1. The rates of growth of Bardeen Chemicals for the past five years are 5.2 percent, 8.7 percent, 3.9 percent, 6.8 percent, and 19.5 percent. What is the arithmetic mean annual growth rate? What is the geometric mean annual growth rate? Should the arithmetic mean or geometric mean be used to represent the average annual gro

Statistics Problem Set and Signficance Levels

5. The manufacturer of the X-15 steel-belted radial truck tire claims that the mean mileage the tire can be driven before the tread wears out is 60,000 miles. The standard deviation of the mileage is 5,000 miles. The Crosset Truck Company bought 48 tires and found that the mean mileage for their trucks is59,500 miles. Is Crosset

Urgently required--only answers

Determine the decision criterion for rejecting the null hypothesis in the given hypothesis test; i.e., describe the values of the test statistic that would result in rejection of the null hypothesis. Suppose you wish to test the claim that ?d, the mean value of the differences d for a population of paired data, is greater t

Significance level can the manufacturer's claim be refuted

The manufaturer of the new subcompact Clipper claims that it will average "40 or more miles per gallon on the open road". Some of the competitors believe this claim is too high. To investigate, an independent testing agency is hired to conduct hightway mileage tests. A random sample of 64 clippers showed their mean miles per

5 hypothesis test questions

1) The manufacturer of the new subcompact Clipper claims that it will average "40 or more miles per gallon on the open road." Some of the competitors believe this claim is too high. To investigate, an independent testing agency is hired to conduct highway mileage tests. A random sample of 64 clippers showed their mean miles p

To find if there is significant difference in means using t-test

(See attached file for full problem description) --- According to the historical data, the life expectancy in the United States is equal to the life expectancy in the United Kingdom. A new study has been made to see whether this has changed. Records of individuals from the United States who died recently are selected at ran

Statistics Problems

(See attached file for full problem description with all charts) CHAP. 12 18. There are three hospitals in the Tulsa, Oklahoma, area. The following data show the number of outpatient surgeries performed at each hospital last week. At the .05 significance level, can we conclude there is a difference in the mean number of

Alternative and Null Hypotheses

We are doing a team project for our statistics class and our project is about "Math Anxiety". We are stuck on one question and the questions are "the teams will state the null and alternative hypotheses, and the theories that support these hypotheses, that will be tested." If you could please explain what they are asking for and

Hypothesis testing for paired sample of officers

The null and alternate hypotheses are: The following paired observations show the number of traffic citations given for speeding by Officer Dhondt and Officer Meredith of the South Carolina Highway Patrol for the last five months. Day May June July August September Officer Dhondt 30

Hypothesis testing of travelers using e-tickets and complaints

Most air travelers now use e-tickets. Electronic ticketing allows passengers to not worry about a paper ticket, and it costs the airline companies less to handle than a paper ticketing. However, in recent times the airlines have received complaints from passengers regarding their e-tickets, particularly when connecting flights a

Population Survey hypothesis test

The "Washington State Population Survey" is conducted biennially to support research on health care issues and other economic factors affecting Washington State residents. Data from the survey is publicly available and is used extensively in research by many organizations. See link for description of survey if you wish: http://

Formulate Null and Alternative Hypotheses

1. Work through a simple regression calculation using intrinsic job satisfaction and extrinsic job satisfaction. You may USE ALL 288 data points from the DataSet file in Unit 1 or you may select a group of 30 data points. You must provide the 30 data points that you used however or I will be unable to check your work and you wi

ANOVA Uses and Contingency Table

1. Name an application for the use of ANOVA. This can be in a professional setting, hobby, or something you find on the internet 2. What are some business situations where ANOVA would be more appropriate than a Z or T test? 3. Find an example of the use of a contingency table from the internet. Describe what it was test

To state null and alternative hypothesis of given problems

(See attached file for full problem description with all symbols) 1. A coin-operated drink machine was designed to discharge a mean of ounces of coffee per cup. Suppose that we want to carry out a hypothesis test to see if the true mean discharge differs from . State the null hypothesis and the alternative hypothesis that

Testing a Null Hypothesis at 0.1 Significance

A New England Journal of Medicine study found that a substantial portion of acute hospital care is unnecessary. The physicians who conducted the study reviewed the medical records of 1,132 patients hospitalized at six different locations across the country. Overall, 60% of the admissions were judged to be appropriate, 23% were d

To test if the serum helps to cure the disease

2. Two groups, A and B, consist of 100 people each who have a disease. A serum is given to group A but not to group B (which is called the control group); otherwise, the two groups are treated identically. It is found that in groups A and B, 75 and 65 people respectively, recover from the disease. a. At a significance level of

Hypothesis Testing Review - 2 Questions

An investment services company claims that the average annual return on stocks within a certain industry is 11.5%. An investor wants to test whether this claim is true and collects a random sample of 50 stocks in the industry of interest. He finds that the sample average annual return is 10.8% and that the sample standard deviat

Stat Problem

The mean wage of workers in a certain industry over the whole country is $210 per week, with a standard deviation of $7.50. A sample of 100 workers from one large factory is found to have a mean wage of $208 per week. Are the workers in this factory different from the rest of the industry?

Finding population means

Fairfield homes is developing two parcels near Pigeon Fork, Tenn. In order to test different advertising approaches, they use different media to reach potential buyers. The mean annual family income for 75 people making inquires at the first development is $150,000, with a standard deviation of $40,000. A corresponding sample of

Finding the p-value

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, 12 Salespeople were selected at random, and their weekly incomes before and after the plan were recorded. Sid: before $320, after $340 Carol: before $290

Statistical hypothesis testing of temperature instruments

A company compared the performance of two temperature instruments: one coupled to a process computer and the other used for visual control. Ideally, these two instruments should agree. The following data are the two temperatures over a five day period: (see chart in attached file) a. Conduct the most appropriate hypothesis

Statistical processes

1. The yields from an ethanol-water distillation column have a standard deviation of 0.01. Process specifications call for a target yield of 0.93. Management wishes to detect any decrease in the true mean yield. a. A random sample of 8 recent batches produced the following yields. Conduct a hypothesis test to determine