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Hypothesis Testing

Standard Normal Random Variable

Let Z be a standard normal random variable. Determine the value of c such that P (Z > c) = 0.1251 is there a way to do this step by step so i can understand it?

Some hypothesis testing problems

Assume that a hypothesis test of the given claim will be conducted. The college Dean of Admissions claims that the times students require to earn a bachelors degree have a mean less than five years. Which equality/inequality (e.g., =, =<, etc.) would use in the Null Hypothesis? Assume that a hypothesis test of the giv

Hypothesis Test for Means

1. The mean age of bus drivers in Chicago is 54.5 years. If a hypothesis test is performed, how should you interpret a decision that fail to rejects the null hypothesis? A There is sufficient evidence to reject the claim mean = 54.5 B There is not sufficient to reject the claim mean = 54.5 C There is sufficient evidence to

Setting Up For Standard Deviation

The end of the year can be a time of rejoicing, a time of business, and a time of confusion. For most employers, it is a time to conduct open enrollment for its employees. For employers and employees, this can be a very confusing time with all of the options made available for the health care industry. The summary detailed be

Decision Rule

Please show in Excel spreadsheets 1) The restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a stdev of 1 minute. The quailty assurance department found in a sample of 50 customers at another place that the mean waiting time was 2.75 minutes. At a .05

Hypothesis Testing Problem set

1. A company has two different processes that make credit cards. Suspecting that machine B has a higher variability than machine A the manager orders a test to be run. The following data was collected: Machine A Machine B Sample size nA= 30 nB=40 Sample Standar

A large discount chain compares the performance of its credit managers in Ohio and Illinois by comparing the mean dollar amounts owed by customers with delinquent charge accounts in these two states.

1. A large discount chain compares the performance of its credit managers in Ohio and Illinois by comparing the mean dollar amounts owed by customers with delinquent charge accounts in these two states. Two random samples of 10 delinquent accounts are selected from all delinquent accounts in Ohio and Illinois. The sample of O

A pollution-control inspector suspected that a riverside community was releasing semitreated sewage into a river and this, as a consequence, was changing (reducing) the level of dissolved oxygen of the river.

A pollution-control inspector suspected that a riverside community was releasing semitreated sewage into a river and this, as a consequence, was changing (reducing) the level of dissolved oxygen of the river. To check this, he drew 15 randomly selected specimens of river water at a location above the town and another 15 specime

Statistics Review

Statistics questions. Please open word document. Missing details attached (got to do with optimal sample size (n)). Thanks. ----------------------------------- Select the correct answer (letter) to the question from the list of answers on the next page. 1. The ________ is the probability of observing a sample value a

Significance Level and Arithmetic Mean Salaries

One reads that a business school graduate with an undergraduate degree earns more than a high school graduate with no additional education, and a person with a master's degree or a doctorate earns even more. To investigate we select a sample of 25 mid-level managers of companies with less than 200 employees. Their incomes, class

Hypothesis Testing of Power Plant Operations

Consolidated Power, a large electric power utility, has just built a modern nuclear power plant. This plant discharges waste water that is allowed to flow into the Atlantic Ocean. The Environmental Protection Agency has ordered that the waste water may not be excessively warm so that thermal pollution of the marine environment n

Calculations for Hypothesis Testing

Indicate the statistical test, the degrees of freedom, the level of significance, the region of rejection, the critical value, the calculated value of the test statistic, and the probability. Situation A The number of new US book titles increased from almost 47,000 in 1990 to over 48,000 in 1991. However, this was still bel

A psychology researcher who does work in creativity wants to determine whether her sample of 50-year-old adults (N = 150) differs statistically from the population of 50-year-olds in intelligence.

Dear OTA, Please help me with steps. Thanks These problems will follow the hypothesis-testing format that is similar to (but not exactly the same as) the one your textbook uses. 1. A psychology researcher who does work in creativity wants to determine whether her sample of 50-year-old adults (N = 150) differs statis

Understanding Experiments with Two Groups

I do not understand the worksheet for this project. Please explain. I have attached this to the file. Understanding Experiments with Two Groups Twenty sets of depressed twins are obtained for a study on the effects of a new antidepressant. In each twin set, one twin is assigned to receive the drug, and the other is desi

Hypothesis Testing on Schizophrenic Twins

See the attached file. Researchers who are interested in schizophrenia examined 15 pairs of identical twins, where one twin was schizophrenic ("affected") and the other was not ("unaffected"). Through MRI studies, they measured the volumes of several regions and subregions within the twin's brains. The data here contains the

Hypothesis Testing - A market research consultant hired by the Pepsi-Cola Co is interested in determining whether there is a difference between the portions of female and male consumers who favor Pepsi Cola over Coke Classic in a particular urban location.

Need help setting up the problem. I understand the mechanics of the problem, I am having trouble setting up P1 and P2 based on the 2 way table (established from the data). ------------------------------------------------------------------- A market research consultant hired by the Pepsi-Cola Co is interested in determining

Hypothesis Testing with Types of Errors

3. At a food processing plant, a machine produces 10 lb bags of sugar. In this particular process, it is important that the sugar content does not go below 9.9 lbs. In fact, when the bags of sugar are less than 9.9 lbs, maintenance is performed on the machine. Consider a hypothesis test where: Ho: X > 9.9 lbs. (In this c

Traditional Approach of Statistical Analysis

1.An insurance company states that 90% of its claims are settled with 5 weeks. A consumer group selected a random sample of 100 of the company's claims and found 75 of the claims were settled within 5 weeks. Is there enough evidence to support the consumer group's claim that fewer that fewer than 90% of the claims were settled

Variable and Averages

Choose a variable. Before collecting the data, decide what a likely average might be, then complete the following: a. Write a brief statement of purpose of the study b. Define the population c. State the hypotheses for the study d. Select an a value e. State how the sample was selected f. Show the rae data g. Decide which

Hypothesis Testing with Reliability in a Two-Tailed Test

Quarterly customer surveys are taken at a medical center. Each individual department has scores and is comparted to the medical center average. Department of Physical Therapy had scores of 9.14, 9.19 and 7.75 for quarters 1-3 respectively. The medical center had scores of 9.01, 9.00 and 9.05 for quarters 1-3 respectively.

Statistics: Evaluating if a theory is true

At one time, the theory of biorhythms was very popular. The theory behind it is that our lives are affected by three primary cycles: Physical, Emotional, and Intellectual. These three cycles can be plotted as sine waves, beginning at zero on the day that a person is born. When any of the individual cycles is at a high point, the

Hypothesis Testing Methods

Here, you are ready to test the hypothesis you have formulated in your JRT experimental design from the Unit 2 assignment. The task is to adjust and reframe your variables and hypothesis in such a way that it can be adequately demonstrated with collected data (better known as Sekaran's Step #8 in the Research Process). Once yu h

Hypothesis Testing of Mileage

The Environmental Protection Agency (EPA) estimated that the, on average, 1994 Polaris automobile obtains a 35 miles per gallon (mpg) on the highway. However, the company that manufactures the car claims that the EPA has underestimated the Polaris' mileage. To support its assertion, the company randomly selects 50 1994-Polaris

Test hypotheses and sample size requirement

1. A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 150 was taken, and the mean amount spent was $225. Assuming a standard deviation equal to $50, find the 95% confidence interval form, the mean for all such families. 2. In testing the hypothesis,