problem: The small pilot study is run to compare a new drug for chronic pain to one that is presently available. Participants are arbitrarily assigned to receive either the new drug or the currently accessible drug and report improvement in pain on a 5-point ordinal scale: 1 = Pain is much worse, 2 = Pain is slightly worse, 3 = No change, 4 = Pain improved slightly, 5 = Pain much improved. Is there a noteworthy difference in self-reported improvement in pain? Use the Mann-Whitney U test with a 5% level of significance.
New Drug: 4 5 3 3 4 2
Standard Drug: 2 3 4 1 2 3
problem: An observational study is conducted to compare experiences of men and women among the ages of 50-59 years following coronary artery bypass surgery. The participants undergo the surgery and are followed until the time of death, until they are lost to follow-up or up to 30 years, whichever comes first. The given table details the experiences of participating men and women. The data beneath are years of death or years of last contact for men and women.
Find out the survival functions for each and every treatment group by using the Kaplan-Meier approach.
problem: As a graduate student, you will likely be required to complete a thesis or a research project concerning an issue in which you are interested. Therefore, this problem will require you to prepare a hypothetical statistical problem (no data collection required) concerning a health-related issue of your choice. The problem must state a research problem you would wish to pursue, and you must conduct hypothesis testing in order to answer your research problem. To answer this problem, your response must clearly provide the following information:
a) The background paragraph providing sufficient information required to conduct hypothesis testing (ex: mean, standard deviation, sample size, research problem or purpose of the study, and your significance level of .05);
b) The suitable hypothesis statements accurately reflecting your research problem or the aim of your study;
c) The statistical test you would use to resolve the problem. Choose one of the given statistical tests you have learned during this course (ex: t-test, ANOVA, chi-square, Mann-Whitney U test). As well, state your rationale for the selection of this statistical test.
d) The decision rule employed to find out when you would reject the null hypothesis. This decision rule must point out the suitable critical value and degrees of freedom (if applicable). You should as well provide a rationale for your decision rule;
e) The computation of your statistical test based on the information provided in your introductory paragraph. You should show your work.
f) State whether or not you would refuse the null hypothesis and also the reason for your decision. As well, give one statement of conclusion for which you should answer your research problem (this statement is the interpretation of your outcomes).