Show the 4-Step Method in testing significance of mean difference in the following case:  The degree of clinical agreement among physicians on the presence or absence of generalized lymphadenopathy was assessed in 32 randomly selected participants from a prospective study of male sexual contacts of men with acquired immunodeficiency syndrome (AIDS) or an AIDS-related condition (ARC). The total number of palpable lymph nodes was assessed by each of three physicians. Results from two of the three physicians are presented in the table attached. Determine whether there is a systematic difference between the assessments of Doctor A vs. Doctor B using 1% level of significance.

A poll was conducted to investigate opinions about global warming. The respondents who answered yes when asked if there is solid evidence that the earth is getting warmer were then asked to select a cause of global warming. The results are given in the accompanying data table. Use a 0.01 significance level to test the claim that the sex of the respondent is independent of the choice for the cause of global warming. Do men and women appear to agree, or is there a substantial difference? Human activity Natural patterns Don't know Male 310 139 36 Female 335 156 34 Click here to view the chi-square distribution table. Identify the null and alternative hypotheses. Họ: The sex of the respondent and the choice for the cause of global warming are independent. H1: The sex of the respondent and the choice for the cause of global warming are dependent. Compute the test statistic. 0.422 (Round to three decimal places as needed.) Find the critical value(s). (Round to three decimal places as needed.…

Acne is a common skin disease that affects most adolescents and can continue into adulthood. A study compared the effectiveness of three acne treatments and a placebo, all in gel form, applied twice daily for 12 weeks. The study's 517 teenage volunteers were randomly assigned to one of the four treatments. Success was assessed as clear or almost clear skin at the end of the 12 week period. The results of the study can be seen in the table below. Using the appropriate statistical test, determine if there is significant evidence that the four treatments perform differently. If so, how do they compare.

A large company that produces allergy medications claims that Americans lose an average of 40 hours of work to problems related to seasonal allergies. A consumer advocacy group believes that company's claim exhibits self-interest bias. In other words, the advocacy group believes that the actual mean number of missed hours is less than claimed. The advocacy group would like to obtain statistical evidence about this issue and takes a random sample of 100 American workers. They find that these 100 people lost and average of 38 hours due to seasonal allergy symptoms. The standard deviation is 9.5 hours. (c) Based on your selection from part (b), what is the value of the standardized test statistic for this significance test?         (d) Based on your selection from part (b), what is the P-value for this significance test?         (e) What is the correct decision for this test, using a 0.05 level of signifcance?           A) Reject the null hypothesis      B) Do not reject the null…