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Hypothesis Testing

Carver Memorial Hospital

Carver Memorial Hospital's surgeons have a new procedure that they think will decrease the time to perform an appendectomy. A sample of 8 appendectomies using the old method had a mean of 38 minutes with a variance of 36 minutes, while a sample of 10 appendectomies using the experimental method had a mean of 29 minutes with a va

Hypothesis testing proportions

The Web-based company Henrietta Balloons has a goal of processing 96% of its orders on the same day they are received. If 95 out of the next 100 orders were processed on the same day, would this prove that they are exceeding their goal, using a 90% confidence level? A. Choose the Hypothesis B. Specify the Decision R

Students Who Finish an Exam First Get Better Grades

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

Lovastatin Reduces the Risk of Heart Attack

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

Audience Based on Significance Levels

For many years TV executives used the guideline that 30 percent of the audience were watching each of the prime-time networks and 10 percent were watching cable stations on a weekday night. A random sample of 500 viewers in the Tampa-St. Petersburg, Florida, area last Monday night showed that 165 homes were tuned in to the ABC a

Hypothesis regression Testing

Need some assistance proving out and explaining (please show detail). In 2005, Century National Bank needed to identify specific drivers in order to increase customer's participation of their additional offered services. In order to accomplish this Century National Bank randomly selected 60 accounts (with or without Debit c

Hypothesis testing problems using Z and t test

The Board of Surgeons recommends a postoperative examination six months after a prostatectomy. In a sample from the records of Carver Memorial Hospital, follow-up exams were given in 80 out of 200 cases. In a sample of records from HiRent Hospital, follow-up exams were given in 120 out of 200 cases. Normality may be assumed bec

For a right-tail test of means (assume equal variances) the critical value is

Carver Memorial Hospital's surgeons have a new procedure that they think will decrease the time to perform an appendectomy. A sample of 8 appendectomies using the old method had a mean of 38 minutes with a variance of 36 minutes, while a sample of 10 appendectomies using the experimental method had a mean of 29 minutes with a va

Applied Statistics in Business and Economics - Regression

Prepare answers to the following assignments from the e-text, Applied Statistics in Business and Economics, by Doane and Seward: 12.48 In the following regression, X = weekly pay, Y = income tax withheld, and n = 35 McDonald's employees. (a) Write the fitted regression equation. (b) State the degrees of freedom for a two-tai

Hypothesis Statement

An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the aver

Statistics

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 α = .025?

P-value

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

Levels of Significance, Hypothesis and Decision Rule

An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the a

Hypothesis Testing for Population Proportions: Example Problem

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 alpha = .025?

Levels of Significance and p-Values

Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard devi

Important information about Z test for mean

Please provide an explanation and step by step process on how these answers are chosen. In an article appearing in Today's Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selec

Does lovastatin reduce the risk of heart attack

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

Managerial Hypotheses Testabilities

Hypothesis testing has been described by some as the use of statistics to determine the probability that a given hypothesis is true. Is this the case. Are real world managerial hypotheses testable? Do you think you could translate real world managerial problems into a testable framework allowing for the application of the metho

Hypothesis Testing: Widgets Produced Per Shift

Please help with the following problem regarding hypothesis testing. Provide a step by step solution. In a given manufacturing environment there are three shifts which produce X thousands of widgets per eight hour shift. Management is concerned that midnight shift is not keeping up with the other shifts, but the numbers for

Test Statistics: P-Value

1) When the necessary conditions are met, a two-tail test is being conducted to test the difference between two population proportions. the two sample proportions are P1 = 0.25 and P2 = 0.20 and the standard error of the sampling distribution of P1 - P2 is 0.04. the calculated value of the test statistic will be? 2) When the

Statistics

When the necessary conditions are met, a two-tail test is being conducted to test the difference between two populations proportions. The two sample proportions are P1 = 0.25 and P2 = 0.20 and the standard error of the sampling distribution of P1 - P2 is 0.04. the caculated value of the test statistic will be 2. One-way

A one sample test -topic 401K

Identify a research issue, problem, or opportunity that uses either interval or ratio level data (Recall that ratio level data are those data which have an absolute zero. This includes all forms of money, weight, time, or distance.) Some examples of ratio level data include a team member's 401K fund, a team member's stock portfo

Advantages of Accurate Interpretation of Statistics

The types kinds of statistical information collected in your professional setting. Provide examples to illustrate the information/data. b. The advantages of accurate interpretation of statistical information c. How this information is used to improve decision making in your organization

Blockbuster is testing a new policy of waiving all late fees on DVD rentals using a sample of 10 randomly chosen customers. (a) At alpha (a) = .10, does the data show that the mean number of monthly rentals has increased? (b) Is the decision close ? (c) Are you convinced?

Blockbuster is testing a new policy of waiving all late fees on DVD rentals using a sample of 10 randomly chosen customers. (a) At alpha= .10, does the data show that the mean number of monthly rentals has increased? (b) Is the decision close ? (c) Are you convinced? DVDRental Customer No Late fee Late