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Hypothesis Testing

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

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 volumes (in cubic centim

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,

Null and alternative hypotheses

If John Smith is charged with a crime under the U.S. legal system and is brought to trial, what are the null and alternative hypotheses that the judge, the jury, and the prosecution must work under? If the jury decides in favor of John Smith does this mean that he has been proven innocent? What about if the jury finds against hi

Hypothesis Testing: One-tailed and Two-tailed Testing

I've been trying to understand the differences between one tailed and two tailed testing, t and z testing and p value. I think I understood #5 but need some help with #18, 23 and 44. 18. The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the

Calculating Upper and Lower Control Limits

A particular magazine typically has 65% subscription renewals. A new advertising campaign is introduced to see if this can be increased. To monitor renewals, a sample of 300 subscribers is taken each month to see what percentage renew their subscription. What are the upper and lower control limits for a control chart for the

Consequences of Type I and Type II Errors

You are a water quality tester, working for the EPA. You are testing the water in a stream just below the point where a major manufacturing company runs water from its plant into the stream. In particular, you are testing for the presence of a pollutant that is supposed to be held at a mean level of 10 ppm. You test the follo

Z-Statistic, T-Statistic and P-value

1. We have now studied two statistics Z and t. Compare and contrast the use of these two statistical tests, with particular attention to the quantity and quality of the data we use in each test. Is one test better than the other? 2. In research the concept of p value is useful to interpret the results of a hypothesis test.

Statistics - highway mileage obtained from 20 automobiles

The data to the left are the highway mileage obtained from 20 automobiles of the same make and model driven under normal conditions by 20 different owners. a. The sticker on the automobile claims that cars of this type get an average of 30 miles per gallon. However the average of these 20 autos is only 28.6 miles per gallon.

A statistics question

Dear: I need help with the following sample question. Many thanks! Could you offer me related data and detailed explanations to the sub-questions so that I can attack similar problems? Thanks! The question: We will run a regression to test whether the Random Walk Model describes daily adjusted closing prices for S

Statistics Questions

Please see attached file for full problem description. Chapter 10 For Exercises 1 & 3 answer the questions: (a) Is this a one- or two-tailed test? (b) What is the decision rule? (c) What is the value of the test statistic? (d) What is your decision regarding H0? (e) What is the p-value? Interpret it. 1. The following in

ANOVA problems

Please see attached file for full problem description. 1- At LLD Records, some of the market research of college students is done during promotions on college campuses, while other market research of college students is done through anonymous mail, phone, internet, and record store questionnaires. In all cases, for each new C

Hypothesis Testing - Dozenol

The nighttime cold medicine Dozenol bears the label indicating the presence of 600 mg of acetaminophen in each fluid ounce of drug. The Food and Drug administration randomly selected 98 one ounce samples and found that the mean acetaminophen is 575 mg, whereas the standard deviation is 55 mg. Use a 21% significance level and tes

Statistics Review - Multiple Choice - Analysis of variance

1. Variance is... A. The average of the squared deviation from the mean. B. A measure of variability of data values about the mean. C. A measure of dispersion. D. All of the above. F. None of the above. 2. Analysis of variance means... A. We compute the variances of the variables observed in the study.

Testing of hypothesis for proportion

1-Testing for categories with different proportions. Here are the observed frequencies from four categories; 5,10,10,20. Assume that we want to use a 0.05 significance level to test the claim that the four categories have proportions of 0.20, 0.25, 0.25and 0.30, repectively a. What is the null hypothesis? b. What are the expec

Computer-interactive Data Analysis

1-Refer to the table below (Computer-interactive Data analysis) that lists the number of years that U.S president and popes and British monarch (since 1690) lived after their inauguration, election, or coronation. Determine whether the survival times for the three groups differ. See attachment for data. 2q-Archaeology: Skull