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Hypothesis Testing

Statistics: Compare Variation in Two Samples of braking distances of cars

Braking Distances of Cars A random sample of 13 four-cylinder cars is obtained and the breaking distances are measured and found to have a mean of 137.5 ft and a standard deviation of 5.8 ft. A random sample of 12 six-cylinder cars is obtained and the braking distances have a mean of 136.3 ft and a standard deviation of 9.7 f

Inferences About Two Means: Independent Samples

Hypothesis Testing for Cigarette Tax: The mean tar content of a simple random sample of 25 unfiltered king size cigarettes is 21.1 mg, with a standard deviation of 3.2 mg. The mean tar content of a simple random sample of 25 filtered 100 mm cigarettes is 13.2 mg with a standard deviation of 3.7 mg. Use a 0.05 significance

Step 5 of hypothesis testing: Calculating the value of Z

The purpose of Team C's research is to determine why men receive higher salaries than women. Before researching the topic, team c will verify that women do indeed make less than men. According to the wages data set, women consist of only 3 of the top 25 salaries out of 100 samples. The mean women's salary is $24,452 with a stand

Inferences About Two Proportions

A total of 61,647 people responded to an Elle/ MSNBC.com survey. It was reported that 50% of the respondents were women and 50% men. Of the women, 27% said that female bosses are harshly critical; of the men 25% said that female bosses are harshly critical. With this sample data with a 0.05 significance level to test the cla

Statistics

1. Assume that you plan to use a significance level of α = 0.05 to test the claim that p1 = p2, Use the given sample sizes and numbers of successes to find the P-value for the hypothesis test. n1 = 100 n2 = 140 x1 = 41 x2 = 35 a. 0.4211 b. 0.0021 c. 0.0512 d. 0.0086 2. Construct the indicate

Test a Claim About a Mean for weight loss: Sigma Not Known

Is the Diet Practical? When 40 people used the Weight Watchers Diet for one year, their mean weight loss was 3.0 lb and the standard deviation was 4.9 lb. Use a 0.01 significance level to test the claim that the mean weight loss is greater than 0 lb. Based on these results, does the diet appear to be effective? Does the diet app

Hypothesis t testing problems

Question #1 / 9 The mean SAT score in mathematics is . The founders of a nationwide SAT preparation course claim that graduates of the course score higher, on average, than the national mean. Suppose that the founders of the course want to carry out a hypothesis test to see if their claim has merit. State the null hypothesis

conclusion about statistical significance

In Exercise 23-26, form a conclusion about statistical significance. Do not make any formal calculations. Either use results provided or make subjective judgments about the results. 24. Mendel's Genetics Experiment One of Gregor Mendel's famous hybridization experiments with peas yielded 580 offsprings with 152 of those peas

Hypothesis Testing of Mean: FICO credit rating scores

See attached file. Data set attached includes a simple random sample of FICO credit rating scores. As of this writing, the Mean FICO score was reported to be 678. Use a 0.05 significance level to test the claim that the sample of FICO scores comes from a population with a mean equal to 678. H0: H1: Test Statistic [S

Test a Claim about a Proportion in a stem cell survey

Stem Cell Survey - Adults were randomly selected for a Newsweek poll. They were asked if they "favor or oppose using federal tax dollars to fund medical research using stem cells obtained from human embryos." Of those polled, 481 were in favor, 401 were opposed, and 120 were unsure. A politician claims that people don't really u

Cans of regular and diet Coke have the same mean weight

See attached file for complete formulas. 2. Below is the summary information for the weights (in pounds) of regular Coke and diet Coke cans. Test the claim that cans of regular Coke and diet Coke have the same mean weight at a 0.01 level of significance. Regular Coke Diet Coke n1=36 n2=36 s1=0.007507 s2=0.0004391

Reversal - Null and Alternative Hypotheses

1. In the 2000 football season, 247 plays were reviewed by officials using instant video replays, and 83 of them resulted in reversal of the original call. In the 2001 football season, 258 plays were reviewed and 89 of them were reversed. Test the claim that the proportion of plays reversed is different for the 2000 and 2001 s

Hypothesis Testing problems

13. For each of the following: (a) State which two populations are being compared (b) State the research hypothesis (c) State the null hypothesis (d) Say whether you should use a one-tailed or two-tailed test and why. i. In an experiment, people are told to solve a problem by focusing on the details. Is the speed of

Statistics Null hypothesis: 20% of Pennsylvania households make more than $70,000

An economic researcher would like to know whether he can reject the null hypothesis at the 0.10 level, that no more than 20% of the households in Pennsylvania make more than $70,000 per year. a. If 200 Pennsylvania households are chosen at random, how many of them would have to be earning more than $70,000 per year for the r

Stating Conclusions about Claims

In these questions we have to make a decision about the given claim. For example, if the claim is that a coin favors heads and sample results consists of 11 heads in 20 flips, conclude that there is not sufficient enough evidence to support the claim that the coin favors heads. 6) Claim: The proportion of households with tele

Hypothesis testing: Double negative logic, five step process

Can someone explain this material to me in simple terms? (1) Explain the double-negative logic of hypothesis testing (eg: a scientist fails to reject the null hypothesis). (2) What is the five-step process for hypothesis testing? Is the order important? Why or why not?

Statistics tests with conclusions: Florida lot price; Microsoft Outlook users

Problem 6 The Chamber of Commerce of a Florida community advertises that area residential property is available at a mean cost of $25,000 or less per lot. As a part-time resident, you believe this to be an untrue statement and you seek to test the validity of this claim at the .05 level of significance. You collect a sample o

ANOVA: Apple juice concentrate

See attached file. An apple juice manufacturer develops a new juice concentrate. This new product is a) more convenient, b) higher in quality, and c) less expensive than conventional apple juice. The marketing manager needs to decide whether advertising should stress convenience, quality, or price. A pilot study is done in th

Hypothesis Testing: Population proportion

Please explain how you obtained your results. 1. A student wants their College to offer Kickboxing classes as a Physical Education class. To justify that the class is desired he surveys 200 students and finds that 56% would be interested in taking the class. He goes to his Dean and tells him that based on his survey over h

Statistics Case Study -Confidence interval in Minitab

Employee Retention at D&Y Demand for systems analysts in the consulting industry is very strong. Graduates with experience in the consulting business and those who have extensive computer knowledge are getting great offers from consulting companies. Once these people are hired, they frequently switch from one company to ano

General Statistics Null Hypothesis

1 What is the difference between a null hypothesis and an alternative hypothesis? Is the null hypothesis always the same as the verbal claim or assertion that led to the test? Why or why not? 2 For each of the following pairs of null and alternative hypotheses, determine whether the pair would be appropriate for a hypothesis

5-Step Hypothesis Test - 45 Problems

See attached files. I need help answering the following questions. This is all the information that I have to answer these questions. Can you please put the answers to each question under the question in the space provided or pick one of the multiple choice answers or select true or false please. Can you please high lig

5-Step Hypothesis Two-Tailed Z-Test

Using the Autoplex Data Set (See excel spreadsheet attached) determine the Null Hypothesis, Alternative Hypothesis and the Research Question. 1. Null Hypothesis: "There is no difference between the mean price of automobiles bought by younger and older consumers." 2. Alternative Hypothesis: "There is a difference between the

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