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Hypothesis Testing

Testing hypothesis

A statistician was testing the following hypotheses: Ho: μ = 500 vs. Ha: μ ≠ 500. The p-value approach was to be used. A sample of size 49 gave a sample mean of 508. Given that σ = 30 2, and α = 0.01, find the p-value, and write your conclusion.

Hypothesis testing: Athletics, Fishing

Hypothesis Testing: For both problems answer the following. a) What is the level of significance? State null and alternate hypothesis. b) What sampling distribution will you use? do you think the sampling size is sufficiently large? Explain, What is the value of the sample test statistics? c) Find p-value of the test sta

Hypothesis testing: Red Blood Cells, Glucose

For problems 1-2 please provide the following information. a) What is the level of significance? State the null and alternate hypothesis. Will you use left-tailed or right tailed test? b) What sampling distribution will you use? Explain your rational for your choice of sampling distribution. What is the value of the sample

Hypothesis Test: Difference Between Population Proportions

It is asserted that a greater proportion of males (= x 1 ) contribute to charity than females (= x 2 ). A survey of male and female contributors to charity showed that of 900 males surveyed, 86 contributed to charity, and of 1200 females surveyed, 107 contributed to charity. Assume the sample statistics are from random, independ

Question about Statistics: Hypothesis Testing of Political Persuasions

You are curious about whether the professors and students at your school are of different political persuasions, so you take a sample of 20 professors and 20 students drawn randomly from each population. You find that 10 professors say they are conservative, and 6 students say they are conservative. Is this a statistically signi

Hypothesis testing and Level of Significance

Please provide the following information for the following 3 problems: a) What is the level of significance? State the null and alternate hypothesis. b) What sampling distribution will you use? Explain the rationale for your choice of sampling distribution. What is the value of the sample test statistics? c) Find the

Hypothesis testing for Chrysler Concorde Acceleration problem

Chrysler Concorde Acceleration. Consumer reports stated that the mean time for a Chrysler Concorde to go from 0 to 60 miles per hour was 8.7 seconds. a) If you want to set up a statistical test to challenge the claim of 8.7 seconds what would you use for the null hypothesis? b) The town of Leadville, Colorado has an elevat

Scatter Diagram

Make a scatter diagram of the scores, describe in words the general pattern of correlation, if any; figure the correlation coefficient figure whether the correlation is statistically significant (use the .05 significance level, two-tailed); explain the logic of what you have done, writing as if you are speaking to someone who ha

Multiple Choice Questions in Statistics

1. For the hypothesis test, , with n1 = 10 and n2 = 10, the F-test statistic is 2.56. At the 0.01 level of significance, we would reject the null hypothesis. TRUE FALSE 2. If the endpoints of a confidence interval for the difference between a pair of treatment means are both positive numbers, then the

Large Sample Hypothesis Test: Comparing Two Means

A study conducted by the research department of a pharmaceutical company claims that the annual spending (per person) for prescription drugs for allergy relief,is greater than or equal to the annual spending (per person) for non-prescription allergy relief medicine. A health insurance company conducted an independent study and c

Difference of proportion of annual income

Past records suggest that the mean annual income,of teachers in state of Texas is greater than or equal to the mean annual income,of teachers in Virginia. In a current study, a random sample of 25 teachers from Texas and an independent random sample of 25 teachers from Virginia have been asked to report their mean annual income.

Critical value for hypothesis testing

The mean life of a battery used in a digital clock is 305 days. The lives of the battery follow normal distribution. The battery was recently modified to last longer. A sample of 20 of the modified batteries had a mean life of 311 days with a standard deviation of 12 days. The level of significance is .05. What would be your cri

Hypothesis Test for a Population Proportion

A decade-old study found that the proportion, of high school seniors who believed that "getting rich" was an important personal goal was 70% . A researcher decides to test whether or not that percentage still stands. He finds that, among the 240 high school seniors in his random sample, 184 believe that "getting rich" is an impo

Test the hypothesis about the population mean

Finance: P/E of Stocks. The price to earnings ratio(P/E) is an important tool in financial work. A random sample of 14 large U.S. banks gave the following P/E ratios. 24, 16, 22, 14, 12, 13, 17 22, 15, 19, 23, 13, 11, 18 The sample mean is xbar = 17.1( = sign is wavy). Generally speaking, a low P/E " value" or bargain sto

Hypothesis Testing of Manufacturing Bottles

1. In a bottling process, a manufacturer will lose money if the bottles contain either more or, less than is claimed on the label. The quality manager of a plant is interested in testing whether the mean ounces of catsup per family size bottle differ from the label by amount of 20 ounces. A sample of 9 bottles yields a mean fil

Applied Statistics in Business Economics:Water on an Airline

Is the water on your airline flight safe to drink? It is not feasible to analyze the water on every flight, so sampling is necessary. In August and September 2004, the Environmental Protection Agency (EPA) found bacterial contamination in water samples from the lavatories and galley water taps on 20 of 158 randomly selected U.S.

Rejecting the Null Hypothesis: One-Tailed and Two-Tailed Test

Suppose that we observe a random sample size n from a normally distributed population. If we are able to reject H0:µ = µ in favor of a two-tailed alternative hypothesis at the 10% significant level, is it true that we can definitely reject H0 in favor of the appropriate one-tailed alternative at the 5% significant level? Why o

Hypothesis Testing 9. Consider the following hypothesis test: Ho:u > 20 Ho:u < 20 A sample of 50 provided a sample mean of 19.4. The population standard deviation is 2. a. Compute the value of the test statistic. b. What is the p-value? c. Using a = .05, what is your conclusion? d. What is the rejection rule using the critical value? What is your conclusion?

Please see the attached file. 9. Consider the following hypothesis test: Ho:u > 20 Ho:u < 20 A sample of 50 provided a sample mean of 19.4. The population standard deviation is 2. a. Compute the value of the test statistic. b. What is the p-value? c. Using

Hypothesis tests ...

The MacBurger restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a standard deviation of 1 minute. The quality-assurance department found in a sample of 50 customers at the Warren Road MacBurger that the mean waiting time was 2.75 minutes. At the .05 signi

Hypothesis Testing at Different Population Means

Supposed we wish to test H0: µ = 10 vs. H1: µ > 10 at the &#945; = 0.05 significant level. Furthermore, supposed that we observe values of the sample mean and sample standard deviation when n=40 that do not lead to the rejection of H0. Is it true that we might reject H0 if we observed the same values of the sample mean and sam

Hypothesis Testing: Improving Gas Mileage

To test whether a fuel additive improves gas mileage, investigators measured the gas mileage (in miles per gallon) of nine cars with and without the fuel additive. At a level of α = 0.10, can it be concluded that the additive improved gas mileage ? The results are shown below. Car 1 2 3 4 5 6 7 8 9 Gas mileage w

Calculating Test Statistics and checking claim

The data given below are taken from two independent samples collected randomly. Claim: (mu)1 > (mu2)2, alpha = 0.10, sample statistics: x1 (bar) = 500, s1 = 30, n1 = 100 x2 (bar) = 510, s2= 30, n2 = 75 What is the value of test statistics?

Hypothesis Testing for Four Population Means with ANOVA Tables

1) Test to see if four population means are the same or different. Assume the populations are normally distributed and have equal variances. Use the formal hypothesis-testing model. State the conclusion in statistical terms and in conversational English. Use the ANOVA table below. ANOVA Source of Variation SS df MS F

Hypothesis Testing to Increase Significance

See the attached file. 1. To illustrate a production or marketing example: A company stats that is produces cookies with 50 chocolate chips per cookie. A sample of 36 cookies has an average of 49 chips with a standard deviation of 5 chips. Do we have a problem with our advertising claim of 50 chips per cookie (assume a confide

Determining the Confidence Interval and Hypothesis Testing

1.A study with 36 observations had a mean of 70. Assume that the standard deviation is 12. Make a diagram that illustrates the effect of the confidence level on the width of the interval. Use 80%, 90%, 95% and 99%. Summarize what the diagram shows. 2.Computers in some vehicles calculate various quantities related to performa

Null and Alternate Hypothesis

Loretta, who turns this year, has heard that the mean systolic blood pressure among the ...Please see the attached file.

Blood Pressures: Null and Alternate Hypothesis and Type I Errors

A researcher studying stress is interested in the blood pressure measurements of chief executive officers (CEOs) of major corporations. He believes that the mean systolic blood pressure, μ, of CEOs of major corporations is less than 136 mm Hg, which is the value reported in a possibly outdated journal article. He plans to perfo

Small sample hypothesis test for a population mean

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