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Hypothesis Testing

Methods of computation and quantitative ability

A person scores 81 on a test of verbal ability and 6.4 on a test of quantitative ability. For the verbal ability test, the mean for people in general is 50 and the standard deviation is 20. For the quantitative ability test, the mean for people in general is 0 and the standard deviation is 5. Which is this person's stronger abil

Two-tailed tests and further statistical analysis

A coin-operated drink machine was designed to discharge a mean of 6 ounces of coffee per cup. In a test of the machine, the discharge amounts in 14 randomly chosen cups of coffee from the machine were recorded. The sample mean and sample standard deviation were 6.11ounces and .16ounces, respectively. If we assume that the discha

The solution to Test of hypothesis

Given the following hypothesis: Ho: M = 400 H alternative: M not equal to 400 For a random sample of 12 observations, the sample mean was 407 and the sample standard deviation 6. Using the .01 significance level: a. State the decision rule. b. Compute the value of the test statistic. c. What is your decision reg

The answer to One sample Z test

For this exercise 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 H¥ï? E. what is the type p - value? Interpret it. The following information is available. H 10 HÌ > 10 The sample mean is 12

Probability of Individual Scores

Individual scores of a placement examination are normally distributed with a mean of 84.2 and a standard deviation of 12.8. If the score of an individual is randomly selected, find the probability that the score will be less than 90.0. If a random sample of size n = 20 is selected, find the probability that the sample mean

Hypothesis testing and level of measurement

IDENTIFYING LEVEL OF MEASUREMENT There are four levels of measurement, two are numeric and two are attribute data. This first time around, try to identify if a question produces a number or a text number. This not always an easy as you will see. This will be needed later when choosing a hypothesis test. Please attached, I at


Hypothesis test for the difference of population proportions For several decades, it was a common practice in Southern California for houses to be built with pools in the backyard (as any airplane flight which ends at a Southern California airport will reveal). Now, however, that practice may be changing, possibly because of t

What is the p value and can you describe the steps in formal hypothesis testing?

I need help with proving that a population mean is not 150. Use an alpha of 5% and set up the full, detailed, five step hypothesis test. Assume when the sample 200 is taken the sample standard deviation is 10 and the sample mean is 151.77. What is the p value? Describe the steps in formal hypothesis testing. Make at least

Samplings of Pine Trees and Spruce Trees

A field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at the .10 level of significance, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree?

Hypothesis test two sample student t test

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 + The last 24 papers showed a mean score of 69.3 with a standard deviation of 24.9.

Discussions - . Tests of hypothesis for two populations

1. Tests of hypothesis for two populations. List one test statistic that could be used for comparing two populations with hypothesis testing. Can you think of an example where this could be used? 2. Contrary to major television media popular belief, the United States does much good for the world. For example, the United State

Stats and Statistics: confidence intervals, p-values, hypothesis testing.

1. After a sample of numbers is taken from a population, the 95% confidence interval is calculated out at {10.5, 12.0} What is the correct way to interpret this confidence interval? Choose one. (1 point) A) 95% of all values in the population are between 10.5 and 12.0 B) The true population mean has to be between 10.5 and

Hypothesis Testing: Compute P-Value

You want to prove that a population mean is not 7. Data is ratio and a large sample size will be used (n = 225). When the sample is done the sample mean is computed to be 7.2 and the sample standard deviation is 1.5. Test the hypothesis using an alpha of 5%. Use formal hypothesis testing and compute the p-value.

SPSS - Parametric testing, Bonferroni multiple comparison

I need help interpreting the attached SPSS output. Consider the variable for respondents' average income (r inc dol) Is the average income for all respondents 31,126.50? Is the average income for people with less than a high school degree 17,366.97? Is the average income for people with graduate degrees 58,128.38? The

Identify a hypothesis from an article

Start by identifying and summarizing the hypothesis described in the article. Then explain whether the hypothesis was rejected or accepted, and what the implications of this finding are for the study. -----------------------------------------------------------------------------------------------------------------------------

Hypothesis Testing: Age of College Juniors

Develop a problem statement. Let's assume that the question deals with the age of college juniors. 1) Establish the null hypothesis (H0) and the alternate hypothesis (H1). 2) Select the level of significance, that is. 3) Select an appropriate test statistic. 4) Formulate a decision rule based on steps 1, 2,

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

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

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

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

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

Managerial Hypotheses Test-abilities

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

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