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# Hypothesis Testing

### Hypothesis Testing problem for proportion

A study of cats and dogs found that 11 of 50 cats and 21 of 50 dogs slept more than 10 hours per day. At the .05 level of significance, is there sufficient evidence to conclude that a difference exists between the proportion of cats and the proportion of dogs that sleep more than 10 hours per day? A)No, there is not suffici

### Hypothesis Testing

A dietician investigated whether apples washed in hot water or in cold water turned brown at different rates when exposed to air. She took 13 random apples and cut each in half. She washed one half of each apple in hot water and the other half in cold water, and then put both halves out in a tray. Her results (in hours until tu

### The null and alternate hypothesis

Please refer to the attached Excel file.

### Hypothesis testing - A random sample of 10 observations from one population revealed a sample mean of 23 and a sample deviation of 4. A random sample of 8 observations from another population revealed a sample mean of 26 and a sample standard deviation of 5. At the .05 significance level, is there a difference between the population means?

A random sample of 10 observations from one population revealed a sample mean of 23 and a sample deviation of 4. A random sample of 8 observations from another population revealed a sample mean of 26 and a sample standard deviation of 5. At the .05 significance level, is there a difference between the population means?

### P value calculation and interpretation

Gibbs Baby Food Company wishes to compare the weight gain of infants using its brand versus its competitor's. A sample of 40 babies using the Gibbs products revealed a mean weight gain of 7.6 pounds in the first three months after birth. For the Gibbs brand the population standard deviation of the sample is 2.3 pounds. A sample

### 4 questions on Hypothesis testing and SSR, SST

1.Explain how you decide what statement goes into the null hypothesis and what statement go into the alternative hypothesis. 2. What is a critical value? 3. What is Alpha and how is it related to the p-value?

### Test of Hypothesis question

Given the following hypothesis: H0: µ&#8805;20 H1: µ<20 A random sample of five resulted in the following values: 18, 15, 12, 19, and 21. Using the .01 significance level, can we conclude the population mean is less than 20? a. State the decision rule. b. Compute the value of the test statistic. c. What is your d

### Hypothesis Testing : analysis

Given the following hypothesis: H0: µ<10 H1: µ>10 For a random sample of 10 observations, the sample mean was 12 and the sample standard deviation 3. Using the .05 significance level: a. State the decision rule. b. Compute the value of the test statistic. c. What is your decision regarding the null hypothesis?

### Significance Level

The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the average, to assemble a cart. The mean assembly time for a random sample of 24 carts, using the new method, was 40.6 minutes, and the standard deviation of the sample was 2.7 minutes. Using

### Hypothesis Testing

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

### Alternative Hypothesis Testing Claims

Please see the attached file. 4. (a) What is the meaning of the term "null hypothesis". (b) How do you know when to perform a "left-tailed" test in a hypothesis-testing situation versus a "right-tailed" or "two-tailed" test? 5. A hypothesis test is used to tes

### Hypothesis Testing

A bond analyst is analyzing the interest rates for equivalent municipal bonds issued by two different states. At= .05, is there a difference in the interest rates paid by the two states? State A State B Sample size 80 70 Mean interest rate (%) 3.7 4.25 Sample variance

### Hypothesis Testing

66% of students at a university live on campus. A random sample found that 20 of 40 male students and 40 of 50 of female students lived on campus. At the .05 level of significance, is there sufficient evidence to conclude that a difference exists between the proportion of male students who live on campus and the proportion of

### Alternative Hypothesis

A researcher wanted to determine if using an octane booster would increase gasoline mileage. A random sample of seven cars was selected; the cars were driven for two weeks without the booster and two weeks with the booster. Miles /Gal Without Miles / Gal With 21.2 23.8 25.4 25.6 2

### Test Value

A pharmaceutical company is testing the effectiveness of a new drug for lowering cholesterol. As part of this trial, they wish to determine whether there is a difference between the effectiveness for women and for men. At = .05, what is the test value? Women Men Sample size 40 70 Mean effect 7 6.75 Sample variance

### Applied Statistics: Dallas fire trucks, Lovestain drug, student exams, concession stands

10.30 In Dallas some fire trucks were painted yellow instead of red to heighten their visibility. During a test period, a fleet of fire red trucks 153,348 runs and had 20 accidents. While the fleet of yellow trucks made 135,035 runs and had 4 accidents At a (P [Rejecting the null hypothesis |Null hypothesis is true]). =.01 did t

### Variation of Hypothesis

My problem is as follows and is presented in attached Excel file.I tried to cut and past in this descripton box, but all symbols did not transfer, so please refer to the attachment. The following hypotheses are given: H0: &#61555;12 &#8804; &#61555;22 H1: &#61555;12 > &#61555;22 A random sample of 5 observations from

### Test of Hypothesis-Difference Between Means

A South American custom candy producer wants to know if the mean daily consumption of regular sugar sweetened candy eaters is less than that of artificial sweetened candy eaters. Assume the standard deviation for those regular sugar sweetened candy eaters is 1.20 candy products per day and 1.36 for those individuals eating the c

### Test of Hypothesis using a Sample

Marconi Shipping Company packages their shipments in 50 ton containers. History has shown that the shipping department reports that the distribution of container weights follows the normal distribution, and the standard deviation of this process is 3 tons per container. At the end of each day, the shipping coordinator weighs 10

### Hypothesis Test for the Average Salaries of a College Graduates

A college wishes to make the claim that 50% of it's graduates earn more than \$70,000 ten years after graduation. The distribution of salaries of these graduates is completely unknown. A sample of 15 ten year alumni were surveyed and they reported their salaries to be (see attached). Is there evidence, at the 5% significance

Attachments.

### Solution to four hypothesis testing problems

Problem #5 Reis, Inc. Reis, Inc., a New York real estate research firm, tracks the cost of apartment rentals in the United States. In mid-2002, the nationwide mean apartment rental rate was \$895 per month (The Wall Street Journal, July 8, 2002). Assume that, based on the historical quarterly surveys, a population standard de

### A lab technician is tested for her consistency by taking multiple measurements of cholesterol

A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a standard deviation of 1.2 or less. If 20 measurements are taken and their standard deviation is 1.8, is there enough evidence to reject the claim that her standard deviation

### Hypothesis Testing for Grade Point Averages

16.26 Below are grade point averages for 25 randomly chosen university business students during a recent semester. Research question: At &#945; = .01, are the median grade point averages the same for students in these four class levels? GPA Grade Point Averages of 25 Business Students Freshman Sophomore Junior Senior (5 stude

### Hypothesis testing for mean number of miles traveled for employees

As part of a study of corporate employees, the Director of Human Resources for PNC, Inc. wants to compare the distance traveled to work by employees at their office in downtown Cincinnati with the distance for those in downtown Pittsburgh. A sample of 35 Cincinnati employees showed they travel a mean of 370 miles per month, with

### Study Habits - Hypothesis Testing

STUDENT 1 STUDENT 2 STUDENT 3 21 22 10 10 26 23 24 10 23 31 30 26 19 11 10 Need help running the 5 step hypothesis process

### Hypothesis Testing

Please provide Detail (No excel). A metropolitan bus system sampler's rider counts on one of its express commuter routes for a week. Use the following data to establish whether rider ship is evenly balanced by day of the week. Let alpha = 0.05. Day Monday Tuesday Wednesday Thursday Friday Rider Count 10 34 21 57

### Hypothesis Testing Mean Consumptions

Please see the attached file. The mean consumption of beef in 2000 by American adults was 63.5 pounds. A sample of 36 people recently taken yielded the following data, in pounds, on year 2007 beef consumption. Test the claim that the amount of beef consumption has changed since 2000.

### Hypothesis Testing

The 65 students in a class at the University of Soda were given blinded evaluations of pairs of cola drinks. For the 65 comparisons of Coke and Pepsi making up the sample results, Pepsi was preferred 29 times. a. Is the above information sufficient for you to be completely certain that more than 50% of all students at that u