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Hypothesis Testing

Level of Significance (Human Body Temperature Test)

In an article in the Journal of Statistics Education (vol. 4, no. 2, 1996), Allen Shoemaker describes a study that was reported in the Journal of the American Medical Association.* It is generally accepted that the mean body temperature of adult humans is 98.6 degF . In his article, Shoemaker uses the data from the JAM

Hypothesis Testing and Statistical Calculations

1. HO: µ = 70 H1: µ > 70 ? = 20, n = 100, xbar = 80, ? = .01 a) calculate the value of the test statistic b) set up the rejection region. c) determine the p-value d) interpret the results attach file please 2. Draw the operating characteristic curve for n = 10, 50, and 100 for the following test: Ho: ? = 400

Infant Death and Mortality Rates

Is there a significant relationship between the death of infants by race and the cause of death? Infant deaths and mortality rates for the top 3 leading cause of death for African Americans, 2007. (Rates per 100,000 live births) Cause of Death # African African American Non-Hispanic Non-Hispanic Afric

Statistics - Testing with SPSS

A home improvement store recently purchased a new paint color-mixing machine. The machine is rated to produce 6 gallons of mixed paint every minute. The store's manager suspects that the machine is underperforming. In order to test his hypothesis, the manager tests the machine's output by mixing 10 randomly chosen colors and me

Statistics: Sex, Weight, GPA, Smoker and Arm and Leg Length

1) Test of two means. You should select a hypothesis you are interested in testing and then use a test of two means to test this hypothesis. For example, you may be interested in testing whether the GPA of females is higher than that of males in that class. One is going to draw the inference by using a random sample with repl

Hypothesis Testing Problem and Locally Optimum Test

Consider the samples x1, ..., xN which satisfy the following model (see the attachment). x_n - sqrt(0) + w_n; n = 1, ..., N where [w_n] is i.i.d. with corresponding pdf f(w). We are interested in distinguishing between the two hypothesis Ho: theta = 0 and H1: theta > 0. Examine whether a locally optimum test exists that ca

Breaking Strength of Wool Serge Material

The quality control director for a clothing manufacturer wants to study the effect of machines on the breaking strength (in pounds) of wool serge material. A batch of the material is cut into square-yard pieces, and these are randomly assigned, 12 each, to the three machines chosen specifically for the experiment. The results ar

Weight Analyzation of Boston vs Vermont Shingles

The manufacturer of Boston and Vermont asphalt shingles knows that product weight is a major factor in the customer's perception of quality. Moreover, the weight represents the amount of raw materials being used and is therefore very important to the company from a cost standpoint. The last stage of the assembly line packages th

Statistical Analysis and P-Value

A clinical psychologist is treating 25 patients with clinical depression. She wants to find out whether these patients score differently than the general population on an emotional response scale with a population mean, ?= 9.5. She is only interested in whether there is a difference, but not in the direction of the difference a

Null and Alternative Hypothesis for ABC

1) The average salary of managers in the advertising industry is $180,000 per year. Suppose we would like to take a sample of managers at a new company ABC, to see whether the mean annual salary is different from that of the industry. State the null and alternative hypotheses. 2) Suppose a sample of 40 managers at ABC showed

Dummy Variables Required

Please reference attachments to answer the following: Choose Data1 or Data2, and work the following problems: The number of dummy variables is the number of levels of the categorical variable less one because the one left out is quantified by the intercept. Each coefficient of the dummy variables effects a shift in the in

Dow Jones Industrial Average (DJIA)

The data in below represent the closing value of the Dow Jones Industrial Average (DJIA) over the 29 year period from 1979 through 2007. Year Coded Year DJIA 1979 0 838.7 1980 1 964.0 1981 2 875.0 1982 3 1046.5 1983 4 1258.6 1984 5 1211.6 1985 6 1546.7 1986 7 1896.0

Smoking in the US: Hypothesis Testing

Smoking in the United States: Does the survey of the previous question provide good evidence that less than ¼ of all American adults smoked in the week prior to the survey? a. State the hypotheses to be tested b. If your null hypothesis is true, what is the sampling distribution of the sample proportion p-hat? Sketch this d

Setting up variables in SPSS

Ten people were give two tests of balance, first while standing on level ground, and then while standing on a 30 degree slope. Their scores follow. Set up the appropriate variables, and enter the data into SPSS. Participant 1 2 3 4 5 6 7 8 9 10 Score standing on level ground 56 50 41 65 47 50 64 48 47 55 Score standing on

Evaluating Types of Therapy & Results Reported in a Quantitative Study

I'm having problems with these questions. I would like to have the explanations along with solutions. 1. Foa, Rothbaum, Riggs, and Murdock (1991) conducted a study evaluating four different types of therapy for rape victims. The Stress Inoculation Therapy (SIT) group received instructions on coping with stress. The Prolong

Hypothesis Testing: One Sample Tests

Question: The amount of water consumed each day by a healthy adult follows a normal distribution with a mean of 1.20 liters. A sample of 10 adults after the campaign shows the following consumption in liters: - 1.34 1.32 1.38 1.40 1.70 1.40 1.32 1.90 1.38 1.36 At the 0.10 significance level, can we conclu

One Sample Hypothesis Testing on Average Weekly Tips

At the time she was hired as a server at the Grumney Family Restaurant, Beth Brigden was told, "You can average $72 a day in tips." Assume the population of daily tips is normally distributed with a standard deviation of $2.45. Over the first 34 days she was employed at the restaurant, the mean daily amount of her tips was $73.0

Hypothesis Testing on Motor Vehicle Accidents Among College-Age People

A random sample of 400 college students was selected and 120 of them had at least one motor vehicle accident in the previous two years. A random sample of 600 young adults not enrolled in college was selected and 150 of them had at least one motor vehicle accident in the previous two years. At the .05 level, you are testing whet

Evaluating Hypothesis Testing

Scenario: The manager of a package courier service believes that packages shipped at the end of the month are heavier than those shipped early in the month. As an experiment, he weighed a random sample of 20 packages at the beginning of the month. He found that the mean weight was 20.25 pounds and the standard deviation was 5.84

Assembly Line Question

Question: Three assembly lines are used produce a certain component for an airliner. A random sample of six hourly periods are chosen for each assembly line and the number of components produced during these periods for each line is recorded. The output from a statistical software package is: Summary: Groups A - Count-6, Su

Analyzing research data

Attached is a simple spreadsheet I've compiled about the 21 commercial aircraft accidents in the US since 1972 that have at least one survivor and one death. I need help coming up with some good stats. Meaning, please look at the data and crunch the numbers to determine where/if it is safer to sit in the front or the back during

Statistics and Hypothesis Testing

I need help understanding the results. I can't interpret the results and their differences. I attached the whole project so you can see what I am talking about. Results Section : a. The data should be explained in narrative form including what (of importance) was or was not statistically significant. c. Ad

Statistics Problem: Are Visa's new ads successful?

In 2006, Visa wanted to move away from its long running television advertising them of "Visa, it's everywhere you want to be." During the Winter Olympics, Visa featured Olympians in commercials with a broader message, including security; check cards, and payment technologies such as contactless processing. One of the first comme

Short Statistics Problems

3. A chemical engineer is investigating the effect of process operating temperature on product yield. The study results in the following data; use your knowledge of least squares regression to construct a linear model for predicting yield from temperature. These data apply throughout question 3. Temp(Celsius) Yield (

Review of a Statistics Article on Death Certificates

Using the attached article, please help me respond to the following questions: 1. What is the main purpose and hypothesis of the study? 2. Develop a pictorial representation of the relationship between the variables that the authors studied. Include the level of measurement (nominal, ordinal, interval/ratio) for each identi

Probability, hypothesis testing and confidence intervals

What is an important similarity between the uniform and normal probability distributions? A. The mean, median and mode are all equal. B. The mean and median are equal. C. They are negatively skewed. D. About 68% of all observations are within one standard deviation of the mean. The distribution of the annual incomes of a

Hypothesis Testing - Heating and Oil Company

The director of Heating and Oil at Superior Oil Company is concerned about the high cost of home heating oil being offered to their customers for the upcoming Fall season in Philadelphia, PA. The company has no possibility of modifying the oil price under the current economic conditions. He believes that the company should off

Alternative Hypothesis and Level of Significance

Please help me with the following: 1. Write a correct alternative hypothesis for: Ho: µ ? 35. 2. Answer "True" if the statement is always true. If the statement is not always true, replace the words shown in bold with words that make the statement always true. The (1 ? ?) is known as the level of significance of a hypothe

Hypothesis Testing Sample Questions

1. Measurements of the left handed and right handed gripping strengths of twelve left handed persons are recorded as follows. PERSON 1 2 3 4 5 6 7 8 9 10 11 12 LEFT HAND 140 90 125 130 95 121 85 97 131 110 98 109 RIGHT HAND 138 87 110 132 96 120 86 90 129 100 101 117 We wish to test whether left handed persons have greater

Calculating sample size based on population proportion

With a 90% confidence interval, what size sample would we need based on the proportion of population in proportion to sample size? Null hypothesis: There is a taste difference between the two brands so consumers will be able to identify the difference in brand seventy percent of the time. The alternate null hypothesis assert