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Hypothesis Testing

5-Step Hypothesis Tests: t-Test, z-Test and Correlation Hypothesis Test

See attached data file. 1.Choose any published database from either the Census Bureau, the Bureau of Labor Statistics, Federal Statistics, Yahoo! Sports, or any major Web site containing government data, college or professional sports data, or financial data on publicly traded companies. Be sure to cite the source of your dat

Testing of Hypothesis problems

1. A machine produces 5-inch nails. A sample of 12 nails was selected and their lengths determined. The results are as follows: 4.96 4.97 4.87 4.81 4.84 4.89 4.96 4.84 4.86 4.83 4.83 4.91 Assuming that = 0.01, test the hypothesis that the population mean is equal to 5. ?State the null and alternate hypot

Determining Difference in Variances

10.56 A sample of 25 concession stand purchases at the October 22 matinee of Bride of Chucky showed a mean purchase of $5.29 with a standard deviation of $2.78. For the October 26 evening showing of the same movie, for a sample of 25 purchases the mean was $5.12 with a standard deviation of $2.05. The means appear to be very clo

Determine whether the samples are independent or dependent

Determine whether the samples are independent or dependent 1. The effectiveness of a new headache medicine is tested by measuring the amount of time before the headache is cured for patients who use the medicine and another group of patient who use a placebo drug. 2. The effectiveness of a new headache medicine is tested by

Statistical Techniques

A United Nations report shows the mean family income for Mexican migrants to the United States is $27,000 per year. A FLOC(Farm Labor Organizating Committee) evaluation of 25 Mexican family units reveals a mean to be $30,000 with a sample standard deviation of $10,000. Does this information disagree with the United Nations repor

23 Multiple choice Statistics questions

Express the null hypothesis H0 and the alternative hypothesis H1 in symbolic form. Use the correct symbol (u,p, σ) for the indicated parameter. 1) The manufacturer of a refrigerator system for beer kegs produces refrigerators that are supposed to maintain a true mean temperature, u, of 46 degrees F, ideal for a certain t

Population has average weight of 71kgs. Compute a test statistic.

Suppose a population has average weight of 71 kgs. A sampling of that population resulted in the following weights: Weights in kgs 60 62 65 68 69 69 71 72 75 77 c. Find a 95% confidence interval for this sample of data. d. State a null hypothesis comparing the average weights of this sample with the average weight

Hypothesis Testing-Infant Sleep Patterns

Infant Sleep Patterns Explain your choice of answers for the above three situations A study of the sleep patterns of 6-month-old infants in the United States reported a 95% confidence interval for the average amount of time infants sleep (out of every 24 hour period) to be (11.5 hours, 15.2 hours). Suppose we want to t

Need help to write a one page summary of this article.

Need help to write a one page summary of this article. Critic of the article, and include your perception of thoughts of his writing.Please summarize your thoughts or main points to justify your critic. Please reword in own words if paraphrase please include reference in paragraphs and please include in text, citation, an

Hypothesis Test - Problems and Solutions

1. A new cell phone battery is being considered as a replacement for the current one. Ten college student cell phone users are selected to try each battery in their usual mix of "talk" and "standby" and to record the number of hours until recharge was needed. (a) Do these results show that the new battery has significantly longe

Statitics questions

I need help with answering these 9 questions. 1) "µ = 17" is an appropriate null hypothesis. A. True B. False 2) If the p-value is less than a in a two-tailed test, the null should be rejected. A. True B. False 3) A Type II error is committed when we reject a null hypothesis that is true. A

Two Proportion Tests and Means

9.64 An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of pocket patient bill above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the a

Statistics: 15 comprehensive problems

Leave out questions 1, 3, 11 and 12. 1. The value of the z score in a hypothesis test is influenced by a variety of factors. Assuming that all other variables are held constant, explain how the value of z is influenced by each of the following: Increasing the difference between the sample mean and the original population mea

Hypothesis Testing, Type of Error

3) A consumer advocacy group is doing a large study on car rental practices. Among other things, the consumer group would like to do a statistical test regarding the mean monthly mileage of cars rented in the U.S. this year. The consumer group has reason to believe that the mean monthly mileage of cars rented in the U.S. this ye

Hypothesis and T-Testing: Oh Baby! Gifts; Oxnard accounting majors and GPA

The Web-based company Oh Baby! Gifts have a goal of processing 95 percent of its orders on the same day they are received. If 365 out of the next 375 orders are processed on the same day, would this prove that they are exceeding their goal, using α = .01? Explain your decision. AND At Oxnard University, a sample of 1

P VALUE of test for average blue-collar workers annual pay

In the midst of labor-management negotiations, the president of a company argues that the company's blue-collar workers, who are paid an average of $30,000 per year, are well paid because the mean annual income of all blue-collar workers in the country is less than $30,000. That figure is disputed by the union, which does not b

Hypothesis Testing: Remission Time & Depressed Individuals

14) Medical researchers interested in determining the relative effectiveness of two different drug treatments on people with a chronic mental illness established two independent test groups. The first group consisted of 9 people with the illness, and the second group consisted of 12 people with the illness. The first group recei

Hypothesis Testing Proportions and Statistics

9) A decade-old study found that the proportion "P" of high school seniors who believed that "getting rich" was an important personal goal was 80% . A researcher decides to test whether or not that percentage still stands. He finds that, among the 235 high school seniors in his random sample, 182 believe that "getting rich" is

Hypothesis Testing Intermediate Computations

7) An electronics manufacturing process has a scheduled mean completion time of 75 minutes. It is claimed that, under new management, the mean completion time is less than 75 minutes. To test this claim, a random sample of 9 completion times under new management was taken. The sample had a mean completion time of 73 minutes an

Hypothesis Testing Breaking Strengths

5) The breaking strengths of cables produced by a certain manufacturer have a mean of 1775 pounds, and a standard deviation of 55 pounds. It is claimed that an improvement in the manufacturing process has increased the mean breaking strength. To evaluate this claim, 90 newly manufactured cables are randomly chosen and tested,

Statistics: Experimental car bumper and repair incidents

An experimental bumper was designed to reduce damage in low-speed collisions. This bumper was installed on an experimental group of vans in a large fleet, but not on a control group. At the end of a trial period, there were 12 repair incidents (a "repair incident" is an accident that resulted in a repair invoice) for the experim

Statistics: Harmonizing depreciation methods between France, Germany and the UK

In recent years major efforts have been made to standardize accounting practices in different countries; this is called harmonization. In an article in Accounting and Business Research, Emmanuel N. Emenyonu and Sidney J. Gray (1992) studied the extent to which accounting practices in France, Germany, and the United Kingdom are h

Century National Bank Scatter Diagram and Correlations

1) Compute/answer the following about the variables "Balance" and "ATM", fr om the Century National Bank Data Set. a) Develop a scatter diagram that represents the question, do higher balances lead to higher usage of ATMs? b) The coefficient of correlation (interpret) c) The coefficient of determination (interpret) d) Is

Null and Alternative Hypotheses: Hybrid Car, Ohio Hospital

In each case, identify the population parameter about which a claim is made, state the null and alternative hypotheses for a hypothesis test, and indicate whether the hypothesis test will be left-tailed, right-tailed, or two-tailed a. The manufacturer of a new model of hybrid car advertises that the mean fuel consumption i