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    Hypothesis Testing

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    Accepting the null hypothesis or failing to reject it

    Consider the seven steps of hypothesis testing. The final step in the hypothesis-testing process involves deciding whether to reject the null hypothesis. Assuming the null hypothesis is not rejected, what is the difference between accepting the null hypothesis and failing to reject it? Explain your reasoning.

    Statistics Population Defective Parts

    1. If 10% of a population of parts is defective, what is the probability of randomly selecting 80 parts and finding that 12 or more parts are defective? 2. A survey was taken of U.S. companies that do business with firms in India. One of the questions on the survey was: Approximately how many years has your company been tra

    Hypothesis Testing for Teaching Style and Gender

    Please see attached file for proper format and formulas. All work has to be shown. If using SPSS a copy of your output and data file has to be present. Please use formulas. Below is the data that has to be used to answer all of the questions. The participants were 30 statistics students that were randomly selected to parti

    Hypothesis Testing of Variance

    A finance professor claims that there is much more variability in the final exam scores of students taking the introductory finance course as a requirement than for students taking the course as part of a major in finance. Random samples of 16 non-finance majors (group 1) and 10 finance majors (group 2) are taken from the profes

    Hypothesis Testing: Animal Bone & Rock Examples

    1. Four animal bone samples were discovered in the ditch terminals. These bones bore signs of attempts at artificial preservation and might have been in use for a substantial period of time before being placed at Stonehenge. When dated, these bones had a mean age of 3187.5 BC and standard deviation of 67.4 years. Assume that the

    Hypothesis Test

    Stonehenge's main ditch was dug in a series of segments. Excavations at the base of the ditch uncovered a number of antlers which bore signs of heavy use. These antlers could have been used by the builders as picks or rakes. The fact that no primary silt was discovered beneath the antlers suggests that they were buried in the di

    Rejection Region

    How is the rejection region defined and how is that related to the z-score and the p value? When do you reject or fail to reject the null hypothesis? Why do you think statisticians are asked to complete hypothesis testing? Can you think of examples in courts, in medicine, or in your area?

    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 $3.02. 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 $2.14. The means appear to be very close, bu

    10.46

    To test the hypothesis that students who finish an exam first get better grades, Professor Hardtack kept track of the order in which papers were handed in. The first 25 papers showed a mean score of 77.1 with a standard deviation of 19.6, while the last 24 papers handed in showed a mean score of 69.3 with a standard deviation of

    10.44

    Does lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? In a Texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. (a) State the app

    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 Ã?± = .01, did the yellow fire trucks have a significantly low

    Test null hypothesis

    The spotlight effect refers to overestimating the extent to which others notice your appearance or behavior, especially when you commit a social faux pas. Effectively, you feel as if you are suddenly standing in a spotlight with everyone looking. In one demonstration of this phenomenon, Gilovich, Medvec, and Savitsky (2000) aske

    Hypothesis Testing: One population

    4. The US department of education reports that 46% of full-time college students are employed while attending college. A recent survey of 600 full-time students at CCP found that 305 were employed. At a 5% level of significance, test to see if there is sufficient evidence that the proportion of full-time students who are employ

    Z test and hypothesis testing

    Please help with the following problem. The mean waiting time for the drive-through window of a fast-food franchise is believed to be 3.7 minutes. A manager wants to check the time at her particular restaurant. A sample of 75 customers is selected and the sample mean waiting time is 3.57 minutes with a sample standard deviat

    Statistical testing using a level of significance

    System data for a job shop revealed that the average time spent by a job in the shop was approximately n = 5 working days. A random sample of size five is taken with time spent in the shop, 3.7, 4.6, 3.9, 4.1, and 3.8. Is the output consistent with system behavior? (Why?). Construct a statistical test using a level of signific

    Comparing two population variances: Example question

    If a random sample of 5 observations from one population results in a standard deviation of 12 and the other random sample of 7 observations results in a standard deviation of 7, with a significance level of .01 is there a variance in the first population. Looking to see how to layout work in this situation. And how to compare

    Statistics of SPSS file binge.save

    Perform appropriate statistics for each of the following variables in the data file "binge.save" 1) age, 2) gender, 3) race, and 4) class. The choice of statistics should be either percentage with bar chart (for categorical/discrete variables), or the mean and standard deviation for continuous/ratio variables. For categorical v

    Consider a chemical company that wishes to determine whether a new catalyst

    Consider a chemical company that wishes to determine whether a new catalyst, catalyst XA-100, changes the mean hourly yield of its chemical process from the historical process mean of 750 pounds per hour. When five trial runs are made using the new catalyst, the following yields (in pounds per hour) are recorded: 801, 814, 7

    The Video Game Satisfaction Rating Case 2

    Recall that very satisfied customers give the XYZ-Box video game system a composite satisfaction rating that is at least 42. a: Letting mu represent the mean composite satisfaction rating for the XYZ-Box, set up the null and alternative hypotheses needed if we wish to attempt to provide evidence supporting the claim that mu e

    The Crown Bottling Company 2

    The Crown Bottling Company has just installed a new bottling process that will fill 16-ounce bottles of the popular Crown Classic Cola soft drink. Both overfilling and underfilling bottles are undesirable: Underfilling leads to customer complaints and overfilling costs the company considerable money. In order to verify that the

    Hypothesis Testing:The Video Game Satisfaction Rating Case 1

    Recall that very satisfied customers give the XYZ-Box video game system a rating that is at least 42. Suppose that the manufacturer of the XYZ-Box wishes to use the random sample of 65 satisfaction ratings to provide evidence supporting the claim that the mean composite satisfaction rating for the XYZ-Box exceeds 42. a: L

    Determine unit amount.

    ABC Convenient stores uses fixed-time period model to determine order quantity for their popular chewing gum (Supergum). Daily demand for Supergum is 100 units with a standard deviation of 25 units. The review period is 10 days and lead time is 6 days. At the beginning of this review period there are 50 units in stock. If

    Establishing a Hypothesis

    Establishing a Hypothesis Open the SPSS data file "chicago.sav" and identify the following data information: 1. Use the data view to identify the units of analysis in this data set. 2. Use the variable view to identify a) the number of variables in this dataset, b) the meaning of variables "pliceex" and murderer". 3. Use the

    Six Sigma Tools for Testing Statistical Significance in Sleep

    Sam Sleep researcher hypothesizes that people who are allowed to sleep for only four hours will score significantly lower than people who are allowed to sleep for eight hours on a management ability test. He brings sixteen participants into his sleep lab and randomly assigns them to one of two groups. In one group he has partici

    Problems involving the Hypothesis Testing of Means

    1. From a population of cans of coffee marked "12 ounces," a sample of 50 cans was selected and the contents of each can were weighed. The sample revealed a mean of 11.8 ounces with a SAMPLE standard deviation of 0.5 ounces. a. Formulate the hypotheses to test alternative hypothesis that the mean of the population is less than

    Wilcoxson Rank Sum Test

    Please help with a wilcoxon some help in the following. The group is for 65 teachers doing a pretest post and at 12 months knowledge quiz on diversity in the class room...I need the following test (wilcoxon with p value set at 0.05 and any explanation you can offer on any significant findings. I know there are differences