1. A random sample of enrollments from medical schools that specialize in research andfrom those that are noted for primary care is listed. At a=0.05, is there a difference inthe means. Test the claim both by using critical value and p-value methods. Find the95% confidence interval for the two means. Show your calculations in detail andinterpret your findings. (Assume that samples are independent, that variables arenormally distributed and that variances are unequal.)Primary careResearch474 577 605 663783 605 427 728783 467 670 414546 474 371 107813 443565696442 587 293 277692 694277419662 555 527 320884

In hypothesis testing we test the hypothesis regarding population parameter.

Answered: 1. A random sample of enrollments from…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The following statistics are computed by sampling from three normal populations whose variances are equal: (You may find it useful to reference the table and the gtable.) X1 = 30.7, n₁ = 7; X2 = 36.9, n₂ = 8; X3 = 42.9, n3 = 4; MSE = 29.0 a. Calculate 95% confidence intervals for 1 - W2, H1 - H3, and 42 - 3 to test for mean differences with Fisher's LSD approach. (Negative values should be indicated by a minus sign. Round final answers to 2 decimal points.) Population Mean Differences H₁-H₂ H₁ H3 H2 H3 Confidence Interval -12.06 -9.01 Can we conclude that the population means differ? Yes Yes No
Research has shown that, for baseball players, good hip range of motion results in improved performance and decreased body stress. A research article reported on a study of independent samples of 40 professional pitchers and 40 professional position players. For the pitchers, the sample mean hip range of motion was 75.8 degrees and the sample standard deviation was 5.6 degrees, whereas the sample mean and sample standard deviation for position players were 79.9 degrees and 7.2 degrees, respectively. Assuming that the two samples are representative of professional baseball pitchers and position players, test hypotheses appropriate for determining if there is convincing evidence that the mean range of motion for pitchers is less than the mean for position players. (Use ? = 0.05. Use ?1 for pitchers and ?2 for position players.)
Researchers conducted a study to determine whether magnets are effective in treating back pain. Pain was measured using the visual analog scale, and the results shown below are among the results obtained in the study. Higher scores correspond to greater pain levels. Assume that the two samples are independent simple random samples selected from normally distributed populations, and do not assume that the population standard deviations are equal. Complete parts (a) to (c) below. Reduction in Pain Level After Magnet Treatment (u): n=22, x=0.58, s=0.89 Reduction in Pain Level After Sham Treatment (H2): n=22, x=0.51, s = 1.29 OA. Ho: H₁₂ H₁₁₂ H₁₁
A researcher knows that the weights of 6 year olds are normally distributed with m = 20 kg and s = 5.0. She suspects that children in poverty-stricken regions differ from the population. With a sample of n = 25 children, the researcher obtains a mean of 17 kg. Identify and calculate the appropriate test statistic.Make sure to report the degrees of freedom for the statistical test (if appropriate). State your conclusions (use a two-tailed test with a = .05 for all tests). Compute an effect size.
Research has shown that, for baseball players, good hip range of motion results in improved performance and decreased body stress. A research article reported on a study of independent samples of 40 professional pitchers and 40 professional position players. For the pitchers, the sample mean hip range of motion was 75.5 degrees and the sample standard deviation was 5.8 degrees, whereas the sample mean and sample standard deviation for position players were 79.1 degrees and 7.1 degrees, respectively. Assuming that the two samples are representative of professional baseball pitchers and position players, test hypotheses appropriate for determining if there is convincing evidence that the mean range of motion for pitchers is less than the mean for position players. (Use ? = 0.05. Use ?1 for pitchers and ?2 for position players.) State the appropriate null and alternative hypotheses. Find the test statistic and P-value. (Use SALT. Round your test statistic to one decimal place and…
Using traditional methods it takes 8.2 hours to receive a basic flying license. A new license training method using Computer Aided Instruction (CAI) has been proposed. A researcher used the technique on 26 students and observed that they had a mean of 8.0 hours with a variance of 2.89. Is there evidence at the 0.1 level that the technique reduces the training time? Assume the population distribution is approximately normal. Step 5 of 5: Make the decision to reject or fail to reject the null hypothesis.
A researcher takes sample temperatures in Fahrenheit of 16 days from San Francisco (Group 1) and 22 days from Atlanta (Group 2). Test the claim that the mean temperature in San Francisco is less than the mean temperature in Atlanta. Use a significance level of a = 0.10. Assume the populations are approximately normally distributed with unequal variances. You obtain the following two samples of data. Round answers to 4 decimal places. San Francisco 77.4 94.8 77 80.9 84 Ho: M₁ 73.4 84.9 92 60.6 83.6 92.5 76.3 93.4 87.2 81.5 70.4 What are the correct hypotheses? Note this may view better in full screen mode. Select the correct symbols for each of the 6 spaces. Atlanta 85.4 92.8 80.2 87.9 80.6 77.9 72.9 75.9 72.1 76.7 80.4 92.5 75.9 72.1 97.7 89.2 88.1 80 92.2 86 96.2 91.9 p-value H₁: M₁ Based on the hypotheses, find the following: Test Statistic = -0.635 X = 0.2494 × OH₂ The p-value is greater than alpha OF H₂ to alpha. The correct decision is to fail to reject the null hypothesis or The…
You wish to test the following claim (Ha) at a significance level of a 0.01. Ho:H1 = 42 Ha:H1 > H2 You believe both populations are normally distributed, but you do not know the standard deviations for either. However, you also have no reason to believe the variances of the two populations are not equal. You obtain a sample of size n1 = 25 with a mean of M1 = 52.5 and a standard deviation of SD, = 9.1 from the first population. You obtain a sample of size n2 = 18 with a mean of M2 = 48.7 and a standard deviation of SD2 = 5.2 from the second population. What is the test statistic for this sample? (Report answer accurate to three decimal places.) test statistic What is the p-value for this sample? For this calculation, use the conservative under-estimate for the degrees of freedom as mentioned in the textbook. (Report answer accurate to four decimal places.) p-value = The p-value is... O less than (or equal to) a O greater than a This test statistic leads to a decision to... O reject the…
A researcher takes sample temperatures in Fahrenheit of 17 days from New York City and 18 days from Phoenix. Test the claim that the mean temperature in New York City is different from the mean temperature in Phoenix. Use a significance level of α=0.05. Assume the populations are approximately normally distributed with unequal variances. You obtain the following two samples of data. New York City Phoenix 99 94.2 95.5 72 93.2 86.8 102 122.1 85.4 114.4 80 94.7 86.4 89.7 75.4 104.7 79.5 77.6 83.4 106.8 64.3 98.6 65.5 91.5 87.7 82 104 97.7 74.3 64.9 59.5 82 82.8 72 116.2 The Hypotheses for this problem are: H0: μ1 = μ2 H1: μ1μ2 Find the p-value. Round answer to 4 decimal places. Make sure you put the 0 in front of the decimal. p-value =
You are interested in testing whether the average age of household heads is higher in the suburbs than in inner city neighbourhoods. A survey is conducted, and the following results are obtained. In the suburbs, the household heads of the 45 households surveyed had a mean age of 44 with a standard deviation of 15. In the inner city, the mean age of the 40 household heads surveyed was 38 with a standard deviation of 13. Assuming that the populations from which these samples were drawn have equal variances, can you conclude that the difference between the two means is significant at the 95% level of confidence? (a) Write in words and symbols the null and research hypotheses. (b) Assuming the variances of the populations are equal, calculate the value of the Pooled Variance Estimate (PVE). (c) Calculate the value of the standard error for the difference between the two means.
You wish to test the following claim (Ha) at a significance level of a = 0.001. H.:µ1 = µ2 Ha:µ1 # µ2 You believe both populations are normally distributed, but you do not know the standard deviations for either. However, you also have no reason to believe the variances of the two populations are not equal (So use the "pool" option). You obtain the following two samples of data. Sample #1 Sample #2 86.4 60.5 63.3 93.5 94.6 61.1 99.2 55.9 85.8 107 88.9 68.8 88.3 61.9 78.8 59.2 103.8 99.7 74.3 72.5 76.5 62 70.5 80.7 80.2 59.2 64.3 107 89.3 113.2 48.5 95.2 72.1 76.1 115.5 75.1 97.6 88.4 96.4 What is the test statistic for this sample? (Report answer accurate to three decimal places.) test statistic = What is the p-value for this sample? For this calculation, use the P-value reported from the "2-sample t- test" from the technology you are using. (Report answer accurate to four decimal places.) p-value = The p-value is... O less than (or equal to) a greater than a This test statistic leads…
An engineer designed a valve that will regulate water pressure on an automobile engine. The engineer designed the valve such that it would produce a mean pressure of 5.5 pounds/square inch. It is believed that the valve performs above the specifications. The valve was tested on 24 engines and the mean pressure was 5.7 pounds/square inch with a variance of 0.49. A level of significance of 0.01 will be used. Assume the population distribution is approximately normal. Make the decision to reject or fail to reject the null hypothesis.

Recommended textbooks for you

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

Elementary Statistics: Picturing the World (7th E…

Statistics

ISBN:

9780134683416

Author:

Ron Larson, Betsy Farber

Publisher:

PEARSON

The Basic Practice of Statistics

Statistics

ISBN:

9781319042578

Author:

David S. Moore, William I. Notz, Michael A. Fligner

Publisher:

W. H. Freeman

Introduction to the Practice of Statistics

Statistics

ISBN:

9781319013387

Author:

David S. Moore, George P. McCabe, Bruce A. Craig

Publisher:

W. H. Freeman

SEE MORE TEXTBOOKS