A new vaccination is being used in a laboratory experiment to investigate whether it is effective. There are 258 subjects in the study. Is there sufficient evidence to determine if vaccination and disease status are related? Vaccination Status Diseased Not Diseased Total Vaccinated 55 62 117 Not Vaccinated 70 71 141 Total 125 133 258 Copy Data Step 7 of 8: Make the decision to reject or fail to reject the null hypothesis at the 0.025 level of significance.

Suppose the results indicate that the null hypothesis should not be rejected; thus, it is possible that a type II error has been committed. Given the type of error made in this situation, what could researchers do to reduce the risk of this error?   Choose a 0.01 significance level, instead of a 0.05 significance level. Increase the sample size.

A cancer research group surveys a random sample of 400 women more than forty years old to test the hypothesis that 30% in this age group have regularly scheduled mammograms. Test if this hypothesis should be rejected at a 5% significance level if 140 women in the sample respond affirmatively?

6.24 Sleep deprivation, CA vs. OR, Part II. Exercise 6.22 provides data on sleep deprivation rates of Californians and Oregonians. The proportion of California residents who reported insufficient rest or sleep during each of the preceding 30 days is 8.0%, while this proportion is 8.8% for Oregon residents. These data are based on simple random samples of 11,545 California and 4,691 Oregon residents. (a)  Conduct a hypothesis test to determine if these data provide strong evidence the rate of sleep deprivation is different for the two states. (Reminder: Check conditions) (b)  It is possible the conclusion of the test in part (a) is incorrect. If this is the case, what type of error was made?

Three years ago, the average starting salary of a new business graduate with a major in accounting in UAE was 15,000 Dhs. A random sample of 10 accounting graduates from this year's graduating class of ZU is selected. The ZU management wants to determine if the starting salaries have increased in the last three years. Assume that the population of starting salaries in accounting is strongly skewed. Which one of the following tests is appropriate for this problem?   a One-sample t-test   b One-sample z-test   c Either one-sample z-test or one-sample t-test   d Neither one-sample z-test nor one-sample t-test

A comparison between species: Biologists wish to compare the prevalence of a genetic mutation across two species of Neema Toads. In a sample of 6 Neema Toads of Species I, 0.8% had the mutation while in a sample of 14 Neema Toads of Species II, 0.7% showed the mutation. Is there significant evidence to suggest a difference in the prevalence of the mutation across the two species? Conduct a hypothesis test at a significance level of α=0.01α=0.01.a) The hypotheses for this test are: H0: pI - pII = 0Ha: pI - pII ≠ 0 H0: pI - pII = 0Ha: pI - pII < 0 H0: pII = 0.008Ha: pII ≠ 0.008 H0: pI - pII = 0Ha: pI - pII > 0 What is the test statistic for this test?test statistic =  (Report answer accurate to 2 decimal places.)What is the p-value for this test?p-value =  (Report answer accurate to 4 decimal places.)The decision reached is Fail to reject H0 Reject H0 and accept Ha As such, the final conclusion is that The prevalence of the mutation is the same for both species. There is…

A random sample of 400 residents are asked if they are in favor of the proposed 10% vanity tax that will raise badly needed revenue for infrastructure development. If 300 are in favor, test the hypothesis that more than 60% of the voters are in favor of the proposed tax. Using a 0.01 level of significance, what is the appropriate test statistic? Ot=6.12 Ot=-6.12 Oz=6.12 OZ=-6.12

The Personnel Manager of a large corporation believes that regular physical exercise leads to a lower resting pulse rate (and so healthier staff). Data was collected on resting pulse rate and whether or not people exercised regularly for a random sample of 22 employees of the corporation. The results are given below. Exercise regularly Do not exercise regularly 72 62 72 60 63 75 64 60 52 64 80 68 64 84 66 72 62 84 76 60 78 84 (a) Formulate appropriate hypotheses to test if the average resting pulse rate is lower in employees who regularly exercise compared with those who do not. (b) Perform a parametric test of the above hypotheses and draw conclusions based on the P-value of the test. (c) Perform a non-parametric test to analyze the same data. (d) State all underlying assumptions for the tests in parts (b) and (e) and comment on the similarities/differences in the outcomes of the tests.

In one study of smokers who tried to quit smoking with nicotine patch​ therapy, 38 were smoking one year after treatment and 33 were not smoking one year after the treatment. Use a 0.01 significance level to test the claim that among smokers who try to quit with nicotine patch​ therapy, the majority are smoking one year after the treatment. Do these results suggest that the nicotine patch therapy is not​ effective? Null and alternative hypotheses for this test. H0 : p=0.5 / H1 : p>0.5 A) Identify the test statistic for this hypothesis test. B) Identify the P-value for this hypothesis test.

40 people are randomly sent to walk one of four trails. The time (in minutes) they spend completing each trail is recorded in the table below. (a) Test to see if the times needed to complete a trail vary. Use a 0.05 significance level. (b) Test each pair (A/B, A/C, A/D, B/C, B/D, C/D) to see which trails have a statistically significant difference. Indicate your p-value for each comparison, and when the effect is statistically significant (use 0.05 as your significance level), declare which trail of the two takes more time to complete. Trail A - 30, 33, 41, 27, 36, 31, 37, 40, 29, 35 Trail B - 27, 33, 38, 41, 40, 38, 35, 44, 41, 39 Trail C - 25, 34, 41, 39, 32, 30, 36, 35, 27, 33 Trail D - 41, 39, 46, 37, 40, 42, 50, 42, 50, 33, 47, 43