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Hypothesis Testing

Hypothesis Testing of Mean: Shopping Time

1. An article in Baltimore Sun claimed that the typical supermarket trip takes a mean of 22 minutes. Suppose that in an effort to test this claim, you select a sample of 50 shoppers at a Baltimore City Giant. The mean shopping time for the sample of 50 shoppers is 25.36 minutes, with a standard deviation of 7.24 minutes (estimat

Hypothesis Testing: Mean life for a shipment of lightbulbs

The quality-control manager at a light bulb factory needs to determine whether the mean life of a large shipment of light bulbs is equal to 375 hours. The population standard deviation is 100 hours. A random sample of 64 light bulbs indicates a sample mean life of 350 hours. a. At the 0.05 level of significance, is there eviden


Section 7.1 : Introduction to Hypothesis Testing 1. State the claim mathematically. Then write the null and alternative hypothesis. Determine whether the hypothesis test is left-tailed, right-tailed, or two-tailed. (References: Definition of a statistical hypothesis on page 365, example 1 on page 366 and example 3 on page 371;

BioStatistics Risk Factors: HIV Infection

A study was conducted looking at risk factors for HIV infection among intravenous drug users enrolled in a methadone program. The data given below were presented regarding the presence of HIV antibody among 120 non-Hispanic white subjects by total family income as assessed by blood testing at one point in time. Group

The Procedure to Test the Efficacy of Drugs

Two drugs (A,B) are compared for the medical treatment of duodenal ulcer. For this purpose, patients are carefully matched on age, sex, and clinical condition. The treatment results based on 200 matched pairs show that for 89 matched pairs both treatments are effective; for 90 matched pairs both treatments are ineffective; for 5

Hypothesis Testing

Independent random samples taken on two university campuses revealed the following information concerning the average amount of money spent on textbooks during the fall semester. University A University B Sample Size 50

The solution to Hypothesis Testing of Mean & Proportion

1. A certain brand of Green Energy light bulbs was advertised as having an average illumination life-span of 2,500 hours. A random sample of 50 bulbs burned out with a mean life-span of 2,470 hours and a sample standard deviation of 140 hours. With a 0.05 level of significance, is the sample mean less than the advertised mean

Statistics Research and Evaluations: American Insurance Institute, Univ of Toledo

See attached file for table to problem 1. 1. 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

Investigated race and equality of access to clinical trials

Researchers investigated the issue of race and equality of access to clinical trials. The table below shows the population distribution and the numbers of participants in clinical trials involving lung cancer (Based on data from "Participation in Cancer Clinical Trials," by Murthy, Krumholz, and Gross, Journal of the American Me

Testing of Hypothesis and Production Levels

Flash Jolt, a manufacturer of camera equipment, annually introduces new models in the fall of the year. At the conclusion of the Christmas season, retail dealers are contacted regarding their stock on hand of each piece of equipment. It has been discovered that unless 47% of the new equipment ordered by the retailers in the fall

Weight Reducers International: Determine the p-value

A new weight-watching company, Weight Reducers International, advertises that those who join will lose, on average, 10 pounds the first two weeks with a standard deviation of 2.8 pounds. A random sample of 50 people who joined the new Weight reduction program revealed the mean loss to be 9 pounds. At the .05 level of significanc

Statistics: Compare effectiveness of splinting versus surgery for carpal tunnel

A randomized trial was designed to compare the effectiveness of splinting versus surgery in the treatment of carpal tunnel syndrome. Results, given in the below table, are based on evaluations made one year after treatment. Using a 0.05 level of significance (? = 0.05), test the claim that success is independent of the type o

Report on research of increased shipping damage costs

The company has been experiencing increased shipping damage costs. Your team has been instructed to conduct a two-sample test to determine if shipping damages are equal for packages equal to or below 15 pounds (Package A) vs. packages greater than 15 pounds (Package B). The CEO must report to the Board of Directors if the ta

Whole Foods Market Website

Please view MSWord attachment, which is an example of how this task should be. 1. What kind of business (industry / area of commerce) is the company involved in? 2. What kind of statistics information did you find? List them if there's more than one kind. Descr

Null, Alternative Hypotheses & Critical region

The production line that packages boxes of raisins at a snack food manufacturer will be conisdered operating properly if the average weight of the boxes of raisin is 3.5 ounces with a standard deviation of 0.3 ounces. A random sample of 20 boxes showed an average weight of 3.30 ounces. Answer questions 4 and 5 based upon this i

Nondirectional Test

For independent samples of customers of Internet providers A and B, the ages are as listed in file XR11073. Using the 0.05 level of significance in a nondirec- tional test, examine whether the variation in ages could be the same for customers of the two providers. Prov

Hypothesis Testing: Comparison of Standard Deviations

11.70. According to the National Association of Homebuilders, the average life expectancies of a dishwasher and a garbage disposal are about the same: 10 years. Assume that their finding was based on a sample of n1 = 60 dishwashers and n2 = 40 garbage disposals, and that the corresponding sample standard deviations were s1 = 30

Interpret the P-Value using a One-Tail Test for SAT Scores

A study has been conducted to examine the effectiveness of new experimental program for preparing high school students for the Scholastic Aptitude Test. Eighty students have been randomly divided into two groups of 40. The eventual SAT scores for those exposed to the new program and the conventional program are listed in data fi

Statistics: AIU Job Satisfaction Studies. Perform a two-tailed hypothesis test

Using AIU's survey responses from the AIU data set,complete the following requirements in the form of a report: 1. Perform a two-tailed hypothesis test on both the intrinsic and the extrinsic variable's data, using a .05 significance level. 2. Begin by creating a null and an alternate statement. 3. Use Microsoft Excel

Questions about Hypothesis Testing of Mean & Proportion

Please provide explanations in detailed and attach all work on a words doc for explanations. Do all work on excel. 1. You are the manager of a restaurant that delivers pizza to college dormitory rooms. You have just changed your delivery in an effort to reduce the mean time between the order and completion of delivery from t

Using Statistical Techniques to teach computers to workers on an assembly line

A group of workers on a manufacturing assembly line type information into a computer. They take a training class on how to use a computer, especially as related to data entry. You want to understand if the computer training was effective. How would you go about this, using statistical techniques? Explain fully. NOTE: Please u

Hypothesis Test for Population Mean

See attached file - Hypothesis Test for Population Mean Hypothesis Test for Population Mean, σ Known Carry out a hypothesis test for the population mean when the population standard deviation is known. Z-Test: Mean hours Mean Standard Deviation