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Hypothesis Testing

Hypothesis testing: Athletics, Fishing

Hypothesis Testing: For both problems answer the following. a) What is the level of significance? State null and alternate hypothesis. b) What sampling distribution will you use? do you think the sampling size is sufficiently large? Explain, What is the value of the sample test statistics? c) Find p-value of the test sta

Question about Statistics: Hypothesis Testing of Political Persuasions

You are curious about whether the professors and students at your school are of different political persuasions, so you take a sample of 20 professors and 20 students drawn randomly from each population. You find that 10 professors say they are conservative, and 6 students say they are conservative. Is this a statistically signi

Hypothesis testing and Level of Significance

Please provide the following information for the following 3 problems: a) What is the level of significance? State the null and alternate hypothesis. b) What sampling distribution will you use? Explain the rationale for your choice of sampling distribution. What is the value of the sample test statistics? c) Find the

Multiple Choice Questions in Statistics

1. For the hypothesis test, , with n1 = 10 and n2 = 10, the F-test statistic is 2.56. At the 0.01 level of significance, we would reject the null hypothesis. TRUE FALSE 2. If the endpoints of a confidence interval for the difference between a pair of treatment means are both positive numbers, then the

Large Sample Hypothesis Test: Comparing Two Means

A study conducted by the research department of a pharmaceutical company claims that the annual spending (per person) for prescription drugs for allergy relief,is greater than or equal to the annual spending (per person) for non-prescription allergy relief medicine. A health insurance company conducted an independent study and c

Difference of proportion of annual income

Past records suggest that the mean annual income,of teachers in state of Texas is greater than or equal to the mean annual income,of teachers in Virginia. In a current study, a random sample of 25 teachers from Texas and an independent random sample of 25 teachers from Virginia have been asked to report their mean annual income.

Test the hypothesis about the population mean

Finance: P/E of Stocks. The price to earnings ratio(P/E) is an important tool in financial work. A random sample of 14 large U.S. banks gave the following P/E ratios. 24, 16, 22, 14, 12, 13, 17 22, 15, 19, 23, 13, 11, 18 The sample mean is xbar = 17.1( = sign is wavy). Generally speaking, a low P/E " value" or bargain sto

Applied Statistics in Business Economics:Water on an Airline

Is the water on your airline flight safe to drink? It is not feasible to analyze the water on every flight, so sampling is necessary. In August and September 2004, the Environmental Protection Agency (EPA) found bacterial contamination in water samples from the lavatories and galley water taps on 20 of 158 randomly selected U.S.

Rejecting the Null Hypothesis: One-Tailed and Two-Tailed Test

Suppose that we observe a random sample size n from a normally distributed population. If we are able to reject H0:µ = µ in favor of a two-tailed alternative hypothesis at the 10% significant level, is it true that we can definitely reject H0 in favor of the appropriate one-tailed alternative at the 5% significant level? Why o

Hypothesis Testing 9. Consider the following hypothesis test: Ho:u > 20 Ho:u < 20 A sample of 50 provided a sample mean of 19.4. The population standard deviation is 2. a. Compute the value of the test statistic. b. What is the p-value? c. Using a = .05, what is your conclusion? d. What is the rejection rule using the critical value? What is your conclusion?

Please see the attached file. 9. Consider the following hypothesis test: Ho:u > 20 Ho:u < 20 A sample of 50 provided a sample mean of 19.4. The population standard deviation is 2. a. Compute the value of the test statistic. b. What is the p-value? c. Using

Hypothesis Testing: Improving Gas Mileage

To test whether a fuel additive improves gas mileage, investigators measured the gas mileage (in miles per gallon) of nine cars with and without the fuel additive. At a level of α = 0.10, can it be concluded that the additive improved gas mileage ? The results are shown below. Car 1 2 3 4 5 6 7 8 9 Gas mileage w

Hypothesis Testing for Four Population Means with ANOVA Tables

1) Test to see if four population means are the same or different. Assume the populations are normally distributed and have equal variances. Use the formal hypothesis-testing model. State the conclusion in statistical terms and in conversational English. Use the ANOVA table below. ANOVA Source of Variation SS df MS F

Hypothesis Testing to Increase Significance

See the attached file. 1. To illustrate a production or marketing example: A company stats that is produces cookies with 50 chocolate chips per cookie. A sample of 36 cookies has an average of 49 chips with a standard deviation of 5 chips. Do we have a problem with our advertising claim of 50 chips per cookie (assume a confide

Determining the Confidence Interval and Hypothesis Testing

1.A study with 36 observations had a mean of 70. Assume that the standard deviation is 12. Make a diagram that illustrates the effect of the confidence level on the width of the interval. Use 80%, 90%, 95% and 99%. Summarize what the diagram shows. 2.Computers in some vehicles calculate various quantities related to performa

Blood Pressures: Null and Alternate Hypothesis and Type I Errors

A researcher studying stress is interested in the blood pressure measurements of chief executive officers (CEOs) of major corporations. He believes that the mean systolic blood pressure, μ, of CEOs of major corporations is less than 136 mm Hg, which is the value reported in a possibly outdated journal article. He plans to perfo

Quantitative Research Methods

1. Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the night shift than on the days shift. Assume the populations standard deviation for the number of units produced on the days shift is 21 and is 28 on the night shift. A sample of 54 day shift workers

Test Statistics of Consumer Products

A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of cars. In particular, each car has one tire of each brand on

Why is statistical significance not necessarily of practical important difference to a business decision? Give an example and explain. Why do statisticians play only a limited role in deciding whether statistical significance requires a business action?

Why is statistical significance not necessarily of practical important difference to a business decision? Give an example and explain. Why do statisticians play only a limited role in deciding whether statistical significance requires a business action?

Econometrics

Problem: 5-Dec Alaska American America West British Continental 7.74% 7.67% -0.89% -2.52% 4.12% Delta JetBlue Northwest Southwest US Airways 4.45% 3.14% 4.84% 3.53% No Change Estimate the variance of the percent change in airline stock 6-Dec

Statistics - Probability and Hypothesis Testing

1. The mean life of a computer disk drive is 2,000 hours. The standard deviation is 140 hours. Assuming the life-time of the drives to be normally distributed, find the probability of a disk drive lasting more than 1,800 hours. a. .4236 b. .9236 c. .8472 d. .5764 e. .2118 f. None of the above. 2. T

What are the different types of samples?

What is an independent sample? What is a related sample? When should researchers use different hypothesis tests for independent and related samples? Is one type of sample preferable over the other?

Test the claim

I went over to our Provost last week to try to convince him that I have the ability of Extrasensory Perception (ESP). I gave him a deck of 10 cards, numbered 1 to 10, and asked him to shuffle them. Then, he would have to look at each card, and concentrate on the number, one at a time. I let him know that I could read hi

Verbal and Numerical Hypothesis

Formulate a numerical hypothesis of the statement issue. Formulate a verbal hypothesis statement regarding your research issue. The additional information is attached.

Two sample hypothesis question

10.38 A ski company in Vail owns two ski shops, one on the east side and one on the west side. Sales data showed that at the eastern location there were 56 pairs of large gloves sold out of 304 total pairs sold. At the western location there were 145 pairs of large gloves sold out of 562 total pairs sold. (a) Calculate the s

Hypothesis Testing

You will be testing the effects of physical activity on happiness ratings for two groups: one group who participates in physical activity and one group who does not participate in physical activity. You will be drawing two samples: one from the population of people who participate in a structured physical activity program and

Quantitave Research Methods - 1. NBC TV news, in segment on the price of gasoline, reported last evening that the mean price nationwide is $2.50 per gallon for self-serve regular unleaded. A random sample of 35 stations in Milwaukee, Wisconsin, area revealed that the mean price was $2.52 per gallon and that the standard deviation was $0.05 per gallon. At the .05 significance level, can we conclude that the price of gasoline is higher in the Milwaukee area? Determine the p-value. 2. eGolf.com receives an average of 6.5 returns per day from online shoppers. For a sample of 12 days, it received the following number of returns. 0 4 3 4 9 4 5 9 1 6 7 10 At the .01 significance level, can we conclude the mean number of returns is less than 6.5? 3. Traditionally, two percent of the citizens of the United States live in a foreign country because they are disenchanted with U.S. politics or social attitudes. In order to test if this proportion has increased since the September 11, 2001, terror attack, U.S. consulates contacted a random sample of 400 of these expatriates. The sample yields 12 people who report they are living overseas because of political or social attitudes. Can you conclude this data shows the proportion of political motivated expatriates has increased? Use the 0.05 significance level.

1. NBC TV news, in segment on the price of gasoline, reported last evening that the mean price nationwide is $2.50 per gallon for self-serve regular unleaded. A random sample of 35 stations in Milwaukee, Wisconsin, area revealed that the mean price was $2.52 per gallon and that the standard deviation was $0.05 per gallon. At the

Quantitative Research Methods: Estimating Population Mean

A state meat inspector in Iowa has been given the assignment of estimating the mean net weight of packages of ground chuck labeled "3 pounds." Of course, he realizes that the weights cannot be precisely 3 pounds. A sample of 36 packages reveals the mean weight to be 3.01 pounds, with a standard deviation of 0.03 pounds. a.