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Hypothesis Testing

Identify the Hypothesis: Claim of weekly losses

See attached file for better formatting. For the following problem statement, identify the hypothesis H0 and the alternative hypotheses H1. Suppose that a company claims that their weekly losses are no more than $2,500. A sample of 40 random weeks finds a mean weekly loss of $3,200 with an estimated population standard d

Hypothesis Test

A mayor claims that the mean salary for working professionals in the downtown metropolitan area is $42,000. A sample of 35 randomly selected working professionals in the area yields a mean of $39,367 with a sample standard deviation of $7,548. At the a=0.05 significance level, test his claim.

Hypothesis Test: Citical Value

Suppose that a small college claims majority of their students graduate within four years. A random survey of 250 alumni finds that 145 of them graduated within 4 years. Given that the pair of hypotheses that correspond to the claim are as follows: H0: p <= 0.50 H1: p > 0.50 Find the critical values for the hypothesis

Hypothesis Test

Suppose that a company claims that 67% of their employees (about 2/3) buy annual parking permits for parking at their workplace. A random survey of 120 employees finds that 62 of them have annual parking permits. Given that the pair of hypotheses that correspond to the claim are as follows: H0: p = 0.67 H1: p # 0.67 F

Hypothesis Testing for claim about average employee severance package

Please see the attached Word document. Suppose that a company CEO claims that the average severance package for an employee at his company is $500,000. You decide to test his claim using a significance level of a=0.05. A sample of 55 employees yields a mean of =$485,155 with a sample standard deviation of s=$125,575. Firs

Hypothesis Test

Suppose that a small college claims that they graduate at least 500 students every semester. A random sample of 31 semesters yields a sample mean of 420 with a sample standard deviation of 65. H0: m >= 500 Ha: m < 500 Find the critical value for the hypothesis test. Assume that the significance level is a=0.02. Answe

Inference of population mean: Changing electrical field from natural level slows healing Is there good evidence that changing the electrical field from its natural level slows healing?

Inference of population mean: Changing electrical field from natural level slows healing Our bodies have a natural electrical field that is known to help wounds heal. Does changing the field strength slow healing? A series of experiments with newts investigated this question. The data below are the healing rates of cuts (m

Number of bottles and the probability of each number

Please see the attached file for full problem description. 1. Given the number of bottles (0,1,2,3,4) and the probability of each number being overfilled in one month, what is the expected number of overfilled bottles per month? E(X) = SUM(x*P(x)) 2. Given n=4 & p=.3 for a binomial experiment, the

3 Statistics Problems

1. Which hypothesis testing model would be used under each of the following conditions. Use the "model number" from my handout if you wish. By line the information given in each cell is: Level of measurement, number of groups, sample size to be taken, parameter of interest and any qualifications. [Please refer to the attachme

Hypothesis Testing: Legal Services & Sentence Satisfaction

See attached data set. Using AIU's survey responses from the AIU data set, complete the following requirements in the form of a report: Perform a two-tailed hypothesis test on both the legal services satisfaction and the sentence satisfaction variable's data using a .05 significance level. Begin by creating a null and a

Hypothesis Test

A manufacturer is interested in determining whether it can claim that the boxes of detergent it sells contain, on average, more than 500 grams of detergent. From past experience the manufacturer knows that the amount of detergent in the boxes is approximately normally distributed. The firm selects a random sample of 100 boxes an

Null hypothesis for performance of first grade students vs national norm

In comparing the performance of first-grade students in his district with the national norm of 100 on a widely used IQ test, the results for a random sample of his first graders lead him to retain Ho: ? = 100 (? = .01) for his population. He concludes, 'My research proves that the average first grader in our district falls rig

Method process for null hypothesis

Be sure to clearly state your decision on the null hypothesis 1: 9:31: At Oxnard University, a sample of 25 senior accounting majors showed a mean cumulative GPA of 3.25 with a standard deviation of 0.10. At &#945; = .05 in a two-tailed test, does this differ significantly from 3.20 (the mean GPA for all business school sen


Exercise 1 One step in the manufacture of a certain metal clamp involves the drilling of four holes. In a sample of 150 clamps, the average time needed to complete this step was 72 seconds and the standard deviation was 10 seconds. (a) Find the probability that the average time to complete the step is between 65 and 74 sec

Data Analysis

For the following data: Fiscal Year GDP-US ($ billion) Total Spending ($ billion) 1996 7838.5 2719.43 1997 8332.4 2813.59 1998 8793.5 2923.39 1999 9353.5 3053.51 2000 9951.5 3240.18 2001 10286.2 3434.00 2002 10642.3 3697.75 2003 11142.1 3930.63 2004 11867.8 4131.92 2005 12638.4 4397.34 2006 13398.9 4698.23 2007 14

Molar Heat of Fusion of Water; Difference in Diesel Truck Fuel

Exercise 1 Two methods for measuring the molar heat of fusion of water are being compared. Ten measurements made by method A have a mean of 6.02 kilojoules per mole (kJ/mol) with a standard deviation of 0.02 (kJ/mol). Five measurements made by method B have a mean of 6.00 kJ/mol and a standard deviation of 0.01 kJ/mol. a)

5 Step Hypothesis Test

Test the hypothesis that the population average income is greater than $55,000 using 5-step hypothesis test. Given: Sample Mean = $55,450, Sample Standard Deviation = $2,500 Sample Size =121, Significance Level, alpha = 5% State your conclusion in statistical terms and in conversational English. Compute the p-value

5 Step Hypothesis Test

Test the null hypothesis that a population mean is 50 against the alternate hypothesis that the mean is not 50. The data is of ratio level. A sample of 400 showed a sample mean of 51.5 and a sample standard deviation of 10. Use the full, formal hypothesis testing format. What "model" should be used and why?

Inference: Mean study time for first year university students

A class survey in a large class for first year college students asked "About how many minutes do you study on a typical weeknight?" The mean response of the 269 students was x (bar over x) = 137 minutes. Suppose that we know that the study time follows a Normal distribution with standard deviation = 65 minutes in the populatio

Bem Sex-Role Inventory personality test for hotel managers

Successful hotel managers must have personality characteristics often thought of as feminine as well as those often thought of as masculine. The Bem Sex-Role Inventory (BSRI) is a personality test that gives separate ratings for female and male stereotypes, both on a scale of 1 to 7. A sample of 148 male general managers of th

Statistics of Predicting Runs Scored in Baseball

See attached data file. Predicting runs scored in baseball. Statistician Scott Berry built a multiple regression model for predicting total number of runs scored by a Major League Baseball team during a season. Using data on all teams over a 9-year period (a sample of n = 234), the results in the attached table were obtai

Hypothesis Testing of Population Proportion..

Chicken Delight claims that 86 percent of its orders are delivered within 10 minutes of the time the order is placed. A sample of 80 orders revealed that 81 percent were delivered within the promised time. At the .10 significance level, can we conclude that less than 86 percent of the orders are delivered in less than 10 minutes

American Pet Food Dealers Association Data

According to a study by the American Pet Food Dealers Association, 42 percent of U.S. households own pets. A report is being prepared for an editorial in the San Francisco Chronicle. As a part of the editorial a random sample of 265 households showed 175 own pets. Does this data disagree with the Pet Food Dealers Association dat

Hypothesis Testing of Mean.

A researcher claims that the average age of people who buy lottery tickets is 61. A sample of 30 is selected and their ages are recorded as shown below. The standard deviation is 9. At a = 0.05 is there enough evidence to reject the researcher's claim? Show all work. 65 63 75 52 22 80 72 56 82 56 24

Hypothesis Testing: Types of Tests and Errors

Please help with the following questions. What is a one tail test? A two tail test? When are they used? What is a type I error? A type II error? In the hypotheses: Ho: A new auto engine gets the same mpg as an older version Ha: A new auto engine gets more mpg than an older version

T-tests comparing treatment one to treatment two

1. The following data are from an independent-measures experiment comparing two treatment conditions. Do these data indicate a significant difference between the treatments Treatment one: 13 9 7 11 Treatment two: 9 5 5 9 2. A sample of freshmen takes a reading comprehension test and their scores are summarized b