Rhino viruses typically cause common colds. In a test of the effectiveness of​ echinacea, 38 of the 43 subjects treated with echinacea developed rhinovirus infections. In a placebo​ group, 98 of the 114 subjects developed rhinovirus infections. Use a 0.05 significance level to test the claim that echinacea has an effect on rhinovirus infections. Complete parts​ (a) through​ (c) below. Identify the test statistic. z = ______ Identify the p-value p = ______

According to a CCH Unscheduled Absence survey, 9% of small businesses use telecommuting of workers in an effort to reduce unscheduled absenteeism. This proportion compares to 6% for all businesses. Is there really a significant difference between small businesses and all businesses on this issue? Use these data and an alpha of .10 to test this question. Assume that there were 725 small businesses and 875 other businesses in this survey. Appendix A Statistical Tables (Round the intermediate values to 4 decimal places. Round your answer to 2 decimal places.) Observed z = %3D The decision is to

Rhino viruses typically cause common colds. In a test of the effectiveness of​echinacea, 32 of the 38 subjects treated with echinacea developed rhinovirus infections. In a placebo​ group, 84 of the 99 subjects developed rhinovirus infections. Use a 0.05 significance level to test the claim that echinacea has an effect on rhinovirus infections.   Identify the test statistic.   Identify the​ P-value.

An epidemiologist found five cases of “big toe cancer” in the Yukon Territory. Because there were only a few cases, the epidemiologist decided to conduct a matched case-control study to determine whether shoe size larger than 9 is a risk factor for big toe cancer. Cases were individually matched to one control for daily activity, history of athlete’s foot, and history of ingrown toenails. The following data were gathered:  Shoe size > 9 Pair Case Control   1     Yes      No   2      No       No   3      No      Yes   4     Yes     Yes   5      No      Yes Compute the proper measure of association. Interpret your results. If you were to investigate a rare cancer in Lynchburg, where might you look for data? What would be necessary legally and ethically to be able to utilize this data set(s)? Submit your thread by 11:59 p.m. (ET) on Thursday of Module/Week 3, and submit your replies by 11:59 p.m. (ET) on Sunday of the same module/week. 1

Five samples of a ferrous-type substance were used to determine if there is a difference between a laboratory chemical analysis and an X-ray fluorescence analysis of the iron content. Each sample was split into two subsamples and the two types of analysis were applied, with the accompanying results. Assuming that the populations are normal, test at the 0.02 level of significance whether the two methods of analysis give, on the average, the same result. Click here to view the sample analyses. Click here to view page 1 of the table of critical values of the t-distribution. Click here to view page 2 of the table of critical values of the t-distribution. Let sample 1 be the X-ray fluorescence results and let sample 2 be the laboratory chemical results. State the null and alternative hypotheses. Ho: HD H1: HD + Identify the critical region. Select the correct choice below and fill in the answer box(es) to complete your choice. (Round to three decimal places as needed.) O A. t> В. t O C. t<

4. Data were collected from a pretest and posttest of students taking a two-week course in substance abuse. Would you use a t-test (and if so, which one), or would you use ANOVA? Given the following data, complete the exercise to see if there is a significant difference between the two tests. Pretest Posttest 84 90 85 75 70 89 65 91 71 85 72 79 84 88 85 85 66 82 67 99

Rhino viruses typically cause common colds. In a test of the effectiveness of echinacea, 34 of the 39 subjects treated with echinacea developed rhinovirus infections. In a placebo group, 98 of the 115 subjects developed rhinovirus infections. Use a 0.05 significance level to test the claim that echinacea has an effect on rhinovirus infections. Complete parts (a) through (c) below. Identify the test statistic:Z= ___?____ Identify the P-Value: _______State the conclusion about the null hypothesis, as well as the final conclusion that addresses the original claim. _________Identify the confidence interval limits for the appropriate confidence interval.__?____ < P1-P2 < __?____

A reviewer checks to see if a bag of candy weighs less than advertised (e.g., 100 grams). What is the appropriate test statistic for each scenario a. One sample Z-test b. One sample t-test c. two related samples t-test d. two indepdent samples t-test

A researcher is studying the effects of his newly created lens on vision. He samples 9 people with poor vision and measures their visual distance (in feet) with the lens and then without the lens. Did people’s vision with the lens differ from their vision without?   Participant # With Lens Without Lens 1 8 14 2 6 17 3 9 12 4 7 11 5 5 12 6 9 18 7 8 13 8 9 7 9 7 13   What kind of analysis will you use? Why?  State the null and alternative hypothesis.    Check your assumptions. Explain why each of them are or are not met.    Sketch a distribution and shade the rejection region(s), including the corresponding critical value(s).    Using R, calculate your test statistic and interpret the results of your test. (Don’t forget your 95% confidence interval and screenshots of your work!)  What do you conclude about the null hypothesis? Are there significant differences?

What test do I need to run?