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Hypothesis Testing

Test hypotheses and sample size requirement

1. A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 150 was taken, and the mean amount spent was $225. Assuming a standard deviation equal to $50, find the 95% confidence interval form, the mean for all such families. 2. In testing the hypothesis,

Null and Alternative Hypotheses: How Decisions Are Made

If John Smith is charged with a crime under the U.S. legal system and is brought to trial, what are the null and alternative hypotheses that the judge, the jury, and the prosecution must work under? If the jury decides in favor of John Smith does this mean that he has been proven innocent? What about if the jury finds against hi

Hypothesis Testing: One-tailed and Two-tailed Testing

I've been trying to understand the differences between one tailed and two tailed testing, t and z testing and p value. I think I understood #5 but need some help with #18, 23 and 44. 18. The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the

Consequences of Type I and Type II Errors

You are a water quality tester, working for the EPA. You are testing the water in a stream just below the point where a major manufacturing company runs water from its plant into the stream. In particular, you are testing for the presence of a pollutant that is supposed to be held at a mean level of 10 ppm. You test the follo

Z-Statistic, T-Statistic and P-value

1. We have now studied two statistics Z and t. Compare and contrast the use of these two statistical tests, with particular attention to the quantity and quality of the data we use in each test. Is one test better than the other? 2. In research the concept of p value is useful to interpret the results of a hypothesis test.

A statistics question

Dear: I need help with the following sample question. Many thanks! Could you offer me related data and detailed explanations to the sub-questions so that I can attack similar problems? Thanks! The question: We will run a regression to test whether the Random Walk Model describes daily adjusted closing prices for S

Statistics Questions

Please see attached file for full problem description. Chapter 10 For Exercises 1 & 3 answer the questions: (a) Is this a one- or two-tailed test? (b) What is the decision rule? (c) What is the value of the test statistic? (d) What is your decision regarding H0? (e) What is the p-value? Interpret it. 1. The following in

ANOVA problems

Please see attached file for full problem description. 1- At LLD Records, some of the market research of college students is done during promotions on college campuses, while other market research of college students is done through anonymous mail, phone, internet, and record store questionnaires. In all cases, for each new C

Hypothesis Testing - Dozenol

The nighttime cold medicine Dozenol bears the label indicating the presence of 600 mg of acetaminophen in each fluid ounce of drug. The Food and Drug administration randomly selected 98 one ounce samples and found that the mean acetaminophen is 575 mg, whereas the standard deviation is 55 mg. Use a 21% significance level and tes

Statistics Review - Multiple Choice - Analysis of variance

1. Variance is... A. The average of the squared deviation from the mean. B. A measure of variability of data values about the mean. C. A measure of dispersion. D. All of the above. F. None of the above. 2. Analysis of variance means... A. We compute the variances of the variables observed in the study.

Testing of hypothesis for proportion

1-Testing for categories with different proportions. Here are the observed frequencies from four categories; 5,10,10,20. Assume that we want to use a 0.05 significance level to test the claim that the four categories have proportions of 0.20, 0.25, 0.25and 0.30, repectively a. What is the null hypothesis? b. What are the expec

Computer-interactive Data Analysis

1-Refer to the table below (Computer-interactive Data analysis) that lists the number of years that U.S president and popes and British monarch (since 1690) lived after their inauguration, election, or coronation. Determine whether the survival times for the three groups differ. See attachment for data. 2q-Archaeology: Skull

Determine whether there is differences among four tire brands

A Tire Company must determine which of four tire brands supplies the most amount of tire wear. It has been decided that all four tires are to be placed on each of eight cars. This design should allow us to compare tires without having differences in cars affect the comparison. Determine whether there is differences among the

Testing Procedures and Five-Step Hypothesis Testing

Need Help with the following exercises: I have attached the five-step hypothesis testing procedure 14. The null and alternate hypotheses are: H0: 1  2 H1: 1  2 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 17 obse

T-tests , significance and variance

Refer to the real estate data which report information on the homes sold in Denver Colorado year at: .A. At the .05 significance level can we conclude that there is a difference in the mean selling price of the homes with a pool and hoes without a

Hypothesis testing problems - The Rocky Mountain

The Rocky Mountain district sales manager of Rath Publishing, Inc., a college textbook publishing company, claims that the sales representatives make an average of 40 sales calls per week on professors. Several reps say that this estimate is too low. To investigate, a random sample of 28 sales representatives reveals that the

Hypothesis test of a proportion

Please review the attached problem and help. A department store manager claims that at least 45% of persons who visited this store make a purchase. In a sample of 400 persons who visited the store 150 made a purchase. Test the manager's claim at the 3% significance level. a. State the null and alternate hypothesis. b. D


Can you assist me in putting together a z test using the information below ... or if we use a different example? Due to increase in product demand, management needs to increase labor production hours by an estimated 270 hours. Any-Business currently has 30 production employees whose hourly wages varies from $7.50 - $8.50 per

Risk of Drinking Water

In 1854, John Snow, a medical doctor hypothesized that there was a relationship between drinking water supply and cholera in London. The two major companies that supplied water to homes in London both got their water from the Thames River which runs through the city. The Lambeth Company pumped from upstream of London. The Southw

Two-Sample Tests of Hypotheses

Suppose you were the manufacturer of a new and improved light bulb that you claim has an average service life more than twice the life of your nearest competitor's product. You want to test your product to be sure. You test 500 of your bulbs in the lab and find that the average life of your bulbs is 2021 hours. Your competitor c

Statistics- Level of Measurement, parametric (P) or non-parametric (NP).

For the following questions, identify the level of measurement and whether the method to be used for the problem would parametric (P) or non-parametric (NP). Description of Problem a. From a written survey where the respondents were asked to rate an individual on a scale of 1 to 5, one group rated an individual a 3.7, anothe

Hypothesis testing problems

Work should be done in EXcel Refer to the Wage data which report information on the annual wages for a SAMPLE OF 100 WORKERS. ALSO INCLUDED ARE VARIABLES RELATING TO THE INDUSTRY, YEARS OF EDUCATION, AND GENDER FOR EACH OTHER WORKER.(data can be found at

The MacBurger restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a standard deviation of 1 minute. The quality-assurance department found in a sample of 50 customers at the Warren Road MacBurger that the mean waiting time was 2.75 minutes. At the .05 significance level, can we conclude that the mean waiting time is less than 3 minutes?

The MacBurger restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a standard deviation of 1 minute. The quality-assurance department found in a sample of 50 customers at the Warren Road MacBurger that the mean waiting time was 2.75 minutes. At the .05 si

Multiple choice question from hypothesis testing

In chronological order, state the 5 steps of the standard procedure for hypothesis testing: 1. 2. 3. 4. 5. Except as directed, check the single best answer. 6. Which of the following could be a valid null hypotheses? A. &#956; &#8805; 27.9 B. &#956; < 27.9 7. Which of the following can be reject

Null Hypothesis

Please use Excel-----In addition, to showing printouts, state the results of the hypothesis test in terms of the question using complete sentences and examples( I did the other 3?but was'nt so sure about these). 1. The Mac burgher restaurant chain claims that the mean waiting time of customers for service is 3 minutes and a