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Hypothesis Testing

Hypothesis Testing - Shopping Time for Women with Children

The mean shopping time for women with kids is 7.3 minutes. A random sample of women with children in a shopping store gave the following shopping times in minutes: 7.7 8.1 8.2 9.0 5.8 9.3 8.4 6.9 12.1 9.4 8.1 6.2 7.3 7.9 8.2 8.5 7.2 6.3 9.1 8.8 a) Verify that mean=8.1 minutes and s=1.4

Hypothesis Testing: The Claim of Returning to Work

The claim that ""40% of those persons who retired from an industrial job before the age of 60 would return to work if a suitable job was available" is to be investigated at the 0.02 level of risk. If 74 out of the 200 workers sampled said they would return to work, what is our decision? (a) Do not reject the null hypothesis b

Last year the records of Dairy Land Inc., a convenience store chain, showed the mean amount spent by a customer was $30. A sample of 40 transactions this month revealed the mean amount spent was $33 with a standard deviation of $12. At the 0.05 significance level, can we conclude that the mean amount spent has increased? What is the p-value? Follow the five-step hypothesis testing procedure.

Last year the records of Dairy Land Inc., a convenience store chain, showed the mean amount spent by a customer was $30. A sample of 40 transactions this month revealed the mean amount spent was $33 with a standard deviation of $12. At the 0.05 significance level, can we conclude that the mean amount spent has increased? What

In Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility. During a test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents while the fleet of yellow fire trucks made 135,035 runs and had 4 accidents. At α = .01, did the yellow fire trucks ...

10:30: In Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility. During a test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents while the fleet of yellow fire trucks made 135,035 runs and had 4 accidents. At α = .01, did the yellow fire trucks have a signi

Hypothesis testing to compare two populations

11.The company believes that it averages about the same weight per bag in each of two production lines. To test this idea, they will perform a hypothesis test to compare the two lines at the alpha level of 0.05. State the null and alternative hypotheses: 12.If the test calculates a sample Z of 1.69, what is the corresponding

Hypothesis testing - 1.A company is filling bags of rock salt to a level of 50 pounds. It believes that all bags are filled correctly, but would like to use a hypothesis test with an alpha of 0.05 to check this belief. The company will be using samples of 100 bags from each run to do the test. State the null and alternative hypotheses: ...

1.A company is filling bags of rock salt to a level of 50 pounds. It believes that all bags are filled correctly, but would like to use a hypothesis test with an alpha of 0.05 to check this belief. The company will be using samples of 100 bags from each run to do the test. State the null and alternative hypotheses: Is this a

Hypothesis Testing Question

The manufacturer of batteries for aircraft emergency vehicles claims that lifetime of the 1500 batteries that have been manufactured is normally distributed with a mean of at least 30 months and a standard deviation of 3 months. An aircraft manufacturer checks out 25 batteries that they purchased and discovers a sample mean of

Hypothesis Testing for Police Road Blocks

Please see the attached file. Consider the use of Police road blocks to detect people that are driving intoxicated. a. What are the null and alternative hypothesis? b. What are the type I and type II errors in this case? c. Which type of error is more costly? d. Based on your answer to part (c), what value of

Converting z intervals to x intervals

Convert each z interval to x interval a) -2.17<z b) z<1.28 c) -1.99<z<1.44 d) If the weight is 14 would it be a small animal? e) If it is large would you say z value for the weight of the fawn will be close to 0, -2, or 3 explain. What is given is the mean=27.2 kilograms and standard deviation=4.3 kilograms. I at

Statistics - Null Hypothesis..

A man is on trial accused of murder in the first degree. The prosecutor presents evidence that he hopes will convince the jury to reject the hypothesis that the man is innocent. This situation can be modeled as a significance test with the following hypotheses: Ho: The defendant is innocent H1: The defendant is not inn

One Tailed Hypothesis test

To test the hypothesis that students who finish an exam first get better grades, a professor kept track of the order in which paper were handed in. the first 25 paper showed a mean score of 77.1 with a standard deviation of 19.6. the last 24 paper turned in showed a mean score of 69.3 with a standard deviation of 24.9. Is this a

Hypothesis Testing for Incidence of Heart Attacks

Does lovastatin reduce the risk of heart attack? Researchers gave lovastatin to 2,325 people and an placebo to 2,081 people. the average age of both groups in 58 years. After 5 years, 57 of the lavastatin group had suffered a heart attack, compared to 97 from the placebo group. At a=.01, can we conclude that the lovastatin users

F Distribution Test Example

What do we use the F Distribution to test? Provide an example from your place of employment or circle of influence of an instance when you could use the F Distribution.

Hypothesis Testing using Statistical Software Output

Directions: You may include the statistical software output, but you must also include a well-written explanation of the findings. Be sure to answer the question asked in each problem, and explain why, with reference to your output. If you calculate the answers manually, be sure to show your work. I would prefer a Word document

13 Statistics Questions

Please see attachment. Thank you. [1.] A recent article in the Topeka Times reported that 40% of all farms in Kansas will have financial problems this year. A recent survey of 200 farms revealed that 66 of them had financial problems. At the &#945; = 0.01 significance level can we conclude that a smaller proportion of far

Hypothesis Testing Using Alpha and Significance Levels

1) A trucking firm suspects that the mean lifetime of a certain tire uses is less than 35,000miles. To check the claim the firm randomly selects and tests 54 of these tires and gets a mean life time of 34,570 with a standard deviation of 1200 miles. At a alpha = 0.05 test the trucking firms claims. 2) A local brewery distribu

Inflation Rate: Regression

An attempt was made to evaluate the inflation rate as a predictor of the spot rate in the German treasury bill market. For a sample of 29 quarterly observations the estimated linear regression Y hat = 0.0027 + 0.791X was obtained, where Y = the actual change in the spot rate X = Change in the spot rate predicted by

The retailing manager of a supermarket chain wants to determine whether product location has any effect on the sale of pet toys. Three different aisle locations are considered: front, middle, and rear. A random sample of 18 stores is selected, with 6 stores randomly assigned to each aisle location. [See the attached Question file.]

The retailing manager of a supermarket chain wants to determine whether product location has any effect on the sale of pet toys. Three different aisle locations are considered: front, middle, and rear. A random sample of 18 stores is selected, with 6 stores randomly assigned to each aisle location. The size of the display are

Sample Test - A newspaper article discussed the opening of a Whole Foods Market in the Time-Warner building in New York City. The following data compared the prices of some kitchen staples ...

A newspaper article discussed the opening of a Whole Foods Market in the Time-Warner building in New York City. The following data compared the prices of some kitchen staples at the new Whole Foods Market and at the Fairway supermarket located about 15 blocks from the Time-Warner building: Half-gallon milk Whole Foods Pri

Hypothesis Testing - Comparing Miles per Gallon of Gas Types

A research firm wants to compare the miles per gallon of unleaded regular, mid-grade, and super premium gasolines. Because of differences in the performance of different automobiles, seven different automobiles were selected and treated as blocks. Therefore, each brand of gasoline was tested with each type of automobile. The res

Chrysler Concorde: Acceleration Hypothesis Testing

Consumer reports stated that the mean time for a Chrysler Concorde to go from 0 to 60 miles per hour was 8.7 seconds. a) If you want to set up a statistical test to challenge the claim of 8.7 seconds, what would you use for the null hypothesis? b) The town of Leadville, Colorado has an elevation over 10,000 feet. Suppose you

Hypothesis test - mean (single small sample) Operating temp.

The mean operating temperature of an aircraft engine during level cruize is supposed to be 190 degrees. An airline tested one particular engine at randomly selected times. The mean temperature on these 25 tests was 193 degrees, with a standard deviation of 3 degrees. Should the pilot worry about th engine running hot? Conduc

Auto Insurance Quotes- Hypothesis Testing Question

The president of the American Insurance Institute wants to compare the yearly costs of auto insurance offered by two leading companies. He selects a sample of 15 families, some with only a single insured driver, others with several teenage drivers, and pays each family a stipend to contact the two companies and ask for a price q

Hypothesis Testing for mean

The Rutter Nursery Company packages pine bark in 50-pond bags. From a long history, the packaging department reports that the distribution is normal. At the end of each day Jeff Rutter, the production manager, weighs 10 bags. Below are the weights of the 10 bags from today's production. 45.6 47.7 46.3 47.6 46.2 47.4 55.

Hypothesis Testing of Genders Wages

Problem 3: In the population of employee of problem 1, a question was raised on whether male and female above 50 make the same wage. To test this contention, a sample of 25 male and 25 female taken randomly was drawn and the wages found were as follow. Test the Hypothesis that the wages are equal for male and female? Mal

Students t test and hypothesis testing

Please help with the following problem. Provide calculations and explanations. The mean interview time for a standard questionnaire of 31.3 minutes was considered to be excessive so the schedule was revised, yielding a mean interview time for a sample of 40 subjects of 21.3 minutes, with a standard deviation of 1.5 minutes.