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Hypothesis Testing

Statistics Review - Significance Level, P-Value

1. A financial analyst wants to compare the turnover rates, in percent, for shares of oil-related stocks versus other stocks, such as GE and IBM. She selected 32 oil-related stocks and 49 other stocks. The mean turnover rate of oil-related stocks is 31.4 percent and the standard deviation 5.1 percent. For the other stocks, the m

Statistics Review Problem Set

1. The following is a hypothetical set of anxiety scale scores from a population of students being seen at a college counseling center: 5 16 47 6 18 50 9 25 50 10 46 50 12 47 78 What are the Z and the T scores of the person who scored 6? 18? Of the two people who scored 47? Of the person who scored 78? Why is it not a

Statistic Mean and Sampling

Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the afternoon shift than on the day shift. A sample of 54 day-shift workers showed that the mean number of units produced was 345, with a standard deviation of 21. A sample of 60 afternoon-shift workers sh

Statistics Data Help

I am doing a project where I am comparing the accuracy and reproducibility of 3 different force gauges with varied angles and applied pressures. All of the gauges have a 50 lb. capacity. They will all be tested with 0-30 lbs in 5 lb increments of applied load/pressure. They will also be tested at 0 degrees (true perpendicular)

Statistics - Baseball Team Scores

Perform each of the steps below using Excel. Use the collected data from the chart (MLB Statistics) as a sample of the population (Any one statistic you choose). Describe the population that the data represents. Interpret each of your results with a conclusion and decision. Use any statistic on the MLB chart to answer the questi

Statistics Questions

Does correlation equal causation? Why or why not? What is the relationship between correlation and association? What is association? When would you use regression correlation at your place of employment, in your education, or in politics? How do you identify outliers in your data? What are the differences between

Using AIU's large data base of survey responses from unit 2 Individual project (keep in mind this data base is your sample), you will begin testing hypothesis. Complete all of the following:

Using AIU's large data base of survey responses from unit 2 Individual project (keep in mind this data base is your sample), you will begin testing hypothesis. Complete all of the following: 1. Test a hypothesis to see whether the average overall job satisfaction (in the population of all workers in the USA) is equal to 4.5=.

5 Step Hypothesis Testing Procedure

Ms Lisa is the budget director for the New Process Company. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample info: Sales ($) 131 135 146 165 136 142 Audit ($) 130 102 129 143 149 120 139 At the .10 confidence level, canshe conclude that the mea

Solve: Hypothesis Testing

Scenario: Your company must make a decision about a very large investment. An internal study shows that if demand for your product increases substantially from the current levels, new production lines must be set up to meet the demand at a reasonable cost and an acceptable quality level. Trying to meet the demand with current fa

Performing Hypothesis Testing

Using a hypothesis test with a well known 4 step procedure, state your conclusion for the 0.05 significance level: A. Based on responses from 1,015 randomly selected teens, which concluded that 44% of teens say grades are the greatest source of pressure, test the claim that fewer than half of all teens in the population feel

Prenatal alcohol hypothesis testing

Alcohol appears to be involved in a variety of birth defects, including low birth weight and retarded growth. A researcher would like to investigate the effect of prenatal alcohol on birth weight. A random sample of n=16 pregnancy rates is obtained. The mother rats are given daily doses of alcohol. The average weight for the sam

Statistical Significance

Your car gets 29 miles per gallon, one day you see your mileage average is 28 miles per gallon. Is this change statistically significantly and would you look for a reason or is it more of a variation attributed to chance? Another day you see your mileage is 22 miles per gallon - Is this change statistically significantly and

Is there a difference in proportion?

10. The manager of a computer software company wishes to study the number of hours top executives spend at their computer terminals by type of industry. The manager selected a sample of five executives from each of three industries. At the .05 significance level, can she conclude there is a difference in the mean number of hours

Statistics : Hypothesis Testing, Test Statistic and Critical Region

Please help answer the following questions involving statistics. 1. Why do we use hypothesis testing? 2. What is a test statistic and how is it related to a critical value in hypothesis testing? 3. What is the critical region in hypothesis testing and why is it important?

Civics Hypothesis Testing

1) The nationwide mean price for a 3-year old Honda civic is $8,500 with a known standard deviation of $600. You check the newspaper and find nine 3-year old Civics in San Francisco selling for an average price of $9,000. You wonder whether the cost of Civics in San Francisco is higher than the rest of the nation. a) State yo

Test with P-Value

1. To compare the current attitudes toward prayer in the schools, a survey was conducted in four southern California counties {see attached for results}. State your hypotheses and conduct a test for homogeneity of attitudes among the four counties concerning prayer in the schools. Use a P-value in your conclusion. It would N

Hypothesis testing of tires and fuel economy

A taxi company manager is trying to decide if the use of radial tires instead of regular belted tires improves fuel economy. As a test, twelve cars are equipped with belted tires and the cars are driven over a prescribed test course. Without changing drivers the same cars were then equipped with the radial tires and driven once

Test of hypothesis: difference between proportions

A survey was completed to estimate the proportion of residents in support of constructing a new football stadium, at tax payer expense, to accommodate an NFL team in the LA area. It was found that 71 of 100 LA city residents favored the construction while 78 of 135 residents in the rest of the county were in support. Determine i

Research Methods / Statistics: 3. Four experimenters investigated the number of items recalled in a study of short-term memory when comparing some 25 year-old participants (Y) with some 65 year-old participants (O). (Use a two-tailed test.) a) Analyze the data as an independent samples design. b) Analyze the same data set as a matched pairs design.

See attachment for complete question. 3 Four experimenters investigated the number of items recalled in a study of short-term memory when comparing some 25 year-old participants (Y) with some 65 year-old participants (O). (Use a two-tailed test.) For this question you will be assigned data from one of these exp

Psychology Research Methods / Stats - Analyze the Data

2. Pigeons were trained to peck to obtain food. During extinction, one group of 21 pigeons was given a drug that inhibits the protein metabolism necessary for memory, while another group of 21 pigeons was not. The rate of pecking was then analyzed (use a one-tailed test). Does the drug increase the pigeons' pecking behaviour?

Design and Analysis of an Experiment Question

From time to time, one branch office of a company must make shipments to a certain branch office in another state. There are three package delivery services between the two cities where the branch offices are located. Since the price structures for the three delivery services are quite similar, the company wants to compare the d

Health Study on Aspirin

US physicians, health study consisted of two randomized clinical trails in one. the first tested the hypothesis that 345 milligrams of aspirin taken every other day reduces mortality from cardiovascular disease. The second tested whether 50 mg B-carotene taken on alternate days decreases the incidence of cancer. 261,248 male phy


1. A 4-day work week ensure that employees will have one more day that need not be spent at work. One possible result is a reduction in the average number of person leave days taken by employees on a 4-day work schedule. Do the data indicate that this is the case? use the p-value approach in testing to reach your conclusion.