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Hypothesis Testing

Statistics: Testing Magnets for Treating Pain

A study was conducted to determine whether magnets were effective in treating pain. The valves represent pain measurements. Use a 0.05 significance level to test the claim that those given a sham treatment have greater variation in pain reductions than those treated with magnets. Assume that the populations are normally distribu

Statistics: BMI for Miss America

Assume that both samples are independant simple random samples from populations having normal distributions. listed below are body mass indexes (BMI) for miss america winners from two different time periods. Use a 0.05 significance level to test the claim that winners from both time periods have BMI values with the same amount

Independent Measures Significance Test

The following data were obtained from an independent measures study. Determine if there is a significant difference between the treatments. Use a significant level of .01. Treatment 1 Treatment 2 5 6 1 10 2 14 3 12 4 1

Heights of Winners and Runners-Up

Assume that the paired sample data are simple random samples and that the differences have a distribution that is approximately normal. Heights of Winners and Runners-up Listed below are the heights (in inches) of candidates who won presidential elections and the heights of the candidates who were runners up. The data are in

Statistics: Are flights cheaper when scheduled earlier?

Assume that the paired sample data are simple random samples and that the difference have a distribution that is approximately normal. Listed below are the costs (in dollars) of flights from New York (JFK) to San Francisco for US Air, Continental, Delta, United, American, Alaska, and Northwest. Use a 0.01 significance level t

Statistics Problem Set: Rejecting the Null Hypothesis

3. Consider the hypothesis test given by H_0: u = 670 H_1: u does not equal 670 In a random sample of 70 subjects, the sample mean is found to be 678.2. The population standard deviation is known to be omega = 27. (a) Determine the P-value for this test. (Show work) (b) Is there sufficient evidence to

Analyzing sample data

A researcher claims that the average age of people who buy theatre tickets is 39. A sample of 30 is selected and their ages are recorded as shown below. The standard deviation is 8. At a = 0.05 is there enough evidence to reject the researcher's claim? (Show all work please so I am able to understand.) 45 38 40 45 35 37 45

Determining ME of the estimate and confidence level

A confidence interval estimate for the population mean is given to be (37.46, 46.39). If the standard deviation is 11.337 and the sample size is 35, answer each of the following (show all work): (A) Determine the maximum error of the estimate, E. (B) Determine the confidence level used for the given confidence interva

Statistics: White Blood Cell Counts

White blood cell counts are helpful for assessing liver disease, radiation, bone marrow failure, and infectious diseases. Listed below are recorded white blood cell counts. A. Use a 0.01 significance level to test the claim that females and males have different mean blood cell counts B. Construct a 99% confidence interval of t

Medecins Sans Frontières- Statistical Testing

My younger brother had a run in earlier with Medecins Sans Frontières. He narrowly escaped from an adverse verdict by the court. What he wants is that he be left alone to run his small cafe. He asked my oldest brother if he can conduct a survey for him about justice in the Canadian court. An initial survey was perform

Global Warming Survey.

Is there solid evidence that the earth is getting warming? 69% of 731 male resondents answered yes and 70% of 770 female respondents answered yes. Use a 0.05 significance level to test the claim that the percentage of males who answered "yes" is less than the percentage of females who answered "yes".

Manufacturing Models

See the attached file. Outside Magazine tested 10 different models of day hikers and backpacking boots. The following data show the upper support and price for each model tested. Upper support was measured using a rating from 1 to 5, with a rating of 1 denoting average upper support and a rating of 5 denoting excellent upper su

Statistics: Hypothesis Testing Questions

Use the attached excel file which consists of 200 MBA students at Whatsamattu U. The file includes variables regarding students' age, gender, major, GPA, Bachelors GPA, course load, English speaking status, family, weekly hours spent studying. Each of the three assigned problems should be formatted as a one page memo. COMPLE

Formulating Hypotheses

Suppose you hear an old timer say, why, in my days kids were much more respectful and didn't cause as much trouble as they do nowadays! Formulate a hypothesis related to this statement that you could test. How would you test it?

Hypothesis Thinking in the Court System

In the North American court system, a defendant is assumed innocent until proven guilty. In an ideal world, we would expect that the truly innocent will always go free, whereas the truly guilty ones will always be convicted. Now, let us tackle the following questions. In the context of the Type I error and Type II error, can

P-Value Method: Comparing the BMI's of Miss America Winners

Please help with the following problem. Assume that a simple random sample has been selected from a normally distributed population and test the given claim. Use the p-value method for testing hypotheses. Identify the null and alternative hypotheses, test statistic, p-value, critical value, and state the final conclusion.

Examining raw data

Identify the null hypothesis, alternative hypothesis, test statistic, P-value and conclusion about the null hypothesis. Use the P-value method. California Speeding. Listed below are recorded speeds (in mi/h) of randomly selected cars traveling on a section of Highway 405 in Los Angles. That part of the highway has a posted s

Statistics: Evaluating significance using the p-value method

Identify the null hypothesis, alternative hypothesis, test statistic, p-value or critical value, and the conclusion about the null hypothesis. Use the P-value method. Question: When a fair die is rolled many times, the outcomes of 1, 2, 3, 4, 5, and 6 are equally likely, so the mean of the outcomes should be 3.5. The author d

Statistics: Using the p-value method

Question: Identify the null hypothesis, alternative hypothesis, test statistic, P-value or critical conclusion about the null hypothesis and final conclusion that addresses the original claim. Use the p-value method and use the normal distribution as an approximation to the binomial distribution. Gender selection for boys Th

Calculating the Test Statistic Z

Hi, I need assistance finding the value of the test statistic z using the below model: z = p - p / square root pq/n Question: The claim is that more than 75% of adults always wear a seat belt in the front seat. A Harris poll of 1012 adults resulted in 870 who say that they always wear a seat belt in the front seat.

Statistics Problem Set: Hypothesis Testing Using Samples

Problem 1: A study by Hewitt Associates showed that 79% of companies offer employees flexible scheduling. Suppose a researcher believes that in accounting firms this figure is lower. The researcher randomly selects 415 accounting firms and through interviews determines that 303 of these firms have flexible scheduling. With a 1%

Statistics Problem Set: Hypothesis Testing

1. What is the difference in average daily hotel room rates between Minneapolis and New Orleans? Suppose we want to estimate this difference by taking hotel rate samples from each city and using a 98% confidence level. The data for such a study follow. Use these data to produce a point estimate for the mean difference in the hot

What are the alternative and null hypotheses?

What is the alternative hypothesis for a null hypothesis stating that the average time a person keeps a cell phone is, at most, three years? State the null and alternative hypotheses for the following: You are investigating a complaint that "special delivery mail takes too much time" to be delivered.

Hypothesis Test - 1

Blockbuster began a policy of waiving late fees (sort of!) on DVD rentals a while back. A random sample of ten customers is shown in the file Blockdvd.xls with the number each customer rented when there was a late fee and when there was no late fee. Test at ? = .10 whether the data suggest that the monthly mean number of rentals

Test the Hypothesis: Eye Exercises and Peripheral Vision

A researcher conducted an experiment to see if specific eye exercises can improve peripheral vision. A random sample of 5 people were rated for peripheral vision on a scale of 1-20, where 9 is considered average and higher scores indicate better peripheral vision. Then they followed the prescribed eye exercise program and were r

Testing a Hypothesis

Researchers have hypothesized that the proverbial rose-colored glasses might indeed help lessen depression caused by light deprivation. A random sample of 39 people suffering from light deprivation depression were given a depression inventory exam, and it was found that on the scale their average measure was 27 with a standard d

Critiquing PERT

You decide to introduce the concept of PERT to a business who is struggling with project scheduling. One of the managers of the company tells you the following: "Well, we thought about PERT before actually. The best part about PERT is that it recognizes uncertainty in project time estimation as it is - there is no attempt to

30 Insulators Level of Significance: Evaluating Force

An organization thinks that if the electrical insulators break when in use, a short circuit might occur. To test the strength of the insulators, a hard core test will be performed to determine how much force is required to break the insulators. Force is measured by observing the number of pounds of force (lbs.) applied to the

Testing Research Hypotheses

Please help with the following problem. In playing the Lemonade Stand Game, Bob decreased his price per cup by two cents, from $.27 per cup to $.25 per cup. At the .05 level of significance, did net revenue increase? The data for weeks 3 and 4 are presented below; there were 30 observations in each week. Items to compar