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    Hypothesis Testing

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    Oh baby! Gifts and Surgical Office Hypothesis Testing Questions

    1. The web based company Oh baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are exceeding their goal, using a=.025? (See story.news.yahoo.com accessed June 25, 2004) 2. An auditor review

    Is the coin biased?

    A coin was flipped 60 times and came up head 38 times (a) at the >10 level of significance, is the coin biased towards heads? Show your decision rule and calculations. (b) calculate a p-value and interpret it.

    Hypothesis Testing: Agreement of Assessments

    Do a complete hypothesis test on the attached problem, including hypothesis, decision rule, calculations of the statistic, decision, interpretation, and p- value. Assume Equal Variances at (alpha) = .025 (using excel) A certain company will purchase the house of any employee who is transferred out of state and will handl

    Tests of Samples with Equal Variance

    A new drug is being tested to see if it reduces the number of migraine headaches. Assuming equal variances, at alpha = .025, do these samples of number of monthly migraines from eight volunteers who are taking the drug and eight who are not show a significant reduction in the mean number of monthly migraine headaches? (See Scien

    10 Multiple choice questions on Hypothesis testing, distributions.

    Please see the attached file for full problem description. 1. If standard deviation (sigma) is unknown when completing a hypothesis test about the population mean, then the best estimate for the unknown standard deviation is s. _____ T/F 2. The chi-square distribution is used for inferences about the population mea

    Hypothesis testing for mean.

    I am looking at this problem that suggests that people will follow a 24 hour cycle of sleeping and waking even if they are not exposed to the usual pattern of sunlight. Their cycles at the end of the study were 25, 27, 25, 23, 24, 25, 26, and 25. If we use the 5% level of significance what would we conclude about the theor

    Two Sample Hypothesis Tests - Womens' Shoe Sizes

    Are women's feet getting bigger? Retailers in the last 20 years have had to increase their stock of larger sizes. Wal-Mart Stores, Inc., and Payless ShoeSource, Inc., have been aggressive in stocking larger sizes, and Nordstrom's reports that its larger sizes typically sell out first. Assuming equal variances, at α = .02

    Two Sample Hypothesis Tests

    A survey of 100 mayonnaise purchasers showed that 65 were loyal to one brand. For 100 bath soap purchasers, only 53 were loyal to one brand. (a) Perform a two-tailed test comparing the proportion of brand-loyal customers at alpha = .05. (b) Form a confidence interval for the difference of proportions, without pooling the sample

    Does Lovastatin reduce the risk of heart attack?

    Does Lovastatin reduce the risk of heart attack? In texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2081 people. After 5 years, 57 of the patients had suffered a heart attack, compared with 97 for the inactive pill. a) State the appropriate hypothesis. b) Obtain a test statistic and

    Hypothesis Testing with the P-Value Approach

    In testing the hypothesis, H0: u _> 28.7 and Ha: u < 28.7, using the p-value approach, a p-value of 0.0764 was obtained. If sigma = 9.8, find the sample mean which produced this p-value given that the sample of size n = 40 was randomly selected.

    Mileage Significance: National Versus Dealer's Average

    In 2004, a small dealership leased 21 Chevrolet Impalas on 2-year leases. When the cars were returned in 2006, the mileage was recorded. Is the dealer's mean significantly greater than the national average of 30,000 miles for 2-year leased vehicles, using the 10 percent level of significance? Mileage 40,060 24,960 14,

    Test of Hypothesis

    Ho:u1-u2 = 0 Ha:u1-u2 does not equal 0 The following results are for two independent samples taken from the two populations. Sample 1 N1 = 80 x1 = 104 o1 = 8.4 Sample 2 N2 = 70 x2 = 106 o2 = 7.6 1. What is the value of the test statistic? 2. What is the p-value 3. With a=.05, what is your co

    Hypothesis Testing: P-Values, Point Estimates, and Error

    1. Consider the following hypothesis test: Ho:u1-u2 = 0 Ha:u1-u2 does not equal 0 The following results are for two independent samples taken from the two populations. Sample 1 N1 = 80 x1 = 104 o1 = 8.4 Sample 2 N2 = 70 x2 = 106 o2 = 7.6 1. What is the value of the test statistic? 2. What is the p-valu

    Hypothesis testing for mean..

    Procyon Mfg. produces tennis balls. Weights are supposed to be normally distributed with a mean of 2.035 ounces and a standard deviation of 0.002 ounces. A sample of 25 tennis balls shows a mean weight of 2.036 ounces. At &#945; = .025 in a right-tailed test, is the mean weight heavier than it is supposed to be?

    Hypothesis testing problems - MacBurger chain & White Industries

    Dear OTA, Please help me with the attached problems with steps. Thanks 1) The MacBurger restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a standard deviation of 1 minute. The quality-assurance department found in a sample of 50 customers at the

    Hypothesis Testing for the American Sugar Producers Association

    1) The American Sugar Producers Association wants to estimate the mean yearly sugar consumption. A sample of 16 people reveals the mean yearly consumption to be 60 pounds with a standard deviation of 20 pounds. 1. What is the value of the population mean? What is the best estimate of this value? 2. Explain why we need to use t

    Test hypothesis

    You are the Vice President for Human Resources at XYZ Investment Management, Inc. Your employees have recently complained about their long working hours. You collected a sample of 49 weekly timesheets and calculated an average of 41.5 hours with a standard deviation of 2.5 hours. Using a significance level of 0.01, can you

    Methodology Involved in Hypothesis Testing

    I need to complete the following - please help me so I can expand on your ideas: Complete and submit a 1000-word report describing the methodology involved in Hypothesis testing. It is required that you include an example of a business situation in which hypothesis testing can utilized.

    Hypothesis Testing: Significance Difference in GPAs

    You conduct a survey of a sample of 25 members of this year's graduating marketing students and find that the average GPA is 3.2. The standard deviation of the sample is 0.4. Over the last 10 years, the average GPA has been 3.0. Is the GPA of this year's students significantly different from the long-run average? At what alpha l

    Testing of hypothesis problems for proportions

    10.2 Find the sample proportions and test statistic for equal proportions. Is the decision close? Find the p-value. a. Dissatisfied workers in two companies: x1 = 40, n1 = 100, x2 = 30, n2 = 100, &#945; = .05, two tailed test. b. Rooms rented at least a week in advance at two hotels: x1 = 24, n1 = 200, x2 = 12, n2 = 50, &#945

    Sample Average and Standard Deviations

    Please do # 2, 3 and 5. 2. In a 2-week study of the productivity of workers, the following data were obtained on the total number of acceptable pieces: 65 36 49 84 79 56 28 43 67 36 43 78 37 40 68 72 55 62 22 82 88 50 60 56 57 46 39 57 73 65 59 48 76 74 70 51 40 75 56 45 35 62 52 63 32 80 64 53 74 34 76 60 48 55 51 54

    Finding Differences in GPAs

    11.3 Semester GPAs are compared for seven randomly chosen students in each class level at Oxnard University. Does the data prove a significant difference in mean GPAs? Please see the attachment and interpret the results. If we are doing a test using a significance level of 5% and we get a p value of less than that- what d

    Conducting a hypothesis test for student math scores

    The mean math score for fifth grade students at Smart Elementary is 90 with a standard deviation of 8. The fifth grade students are tested each year to determine if the mean score remains the same. A random sample of 30 students are chosen from the classes this year and provide a sample mean score of 94. The null hypothesis Ho:

    Agricultural Yield: Hypothesis Testing

    Formulate the null and alternative hypotheses for a hypothesis test. Identify the population and describe how to select a random sample for a hypothesis test. State in clear terms the conclusion that should be given if the null hypothesis is rejected. An agricultural research company claims that the yield for its new breed of

    Formulating Null and Alternative Hypotheses

    Formulate the null and alternative hypotheses for a hypothesis test based on the statement below. Identify the population and describe how to select a random sample for a hypothesis test. State in clear terms the conclusion that should be given if the null hypothesis is rejected. A high school principal claims that the mean m