True story, real data: On Nov. 16. 2020, pharmaceutical company Moderna released interim results of a Phase 3 study of their vaccine for COVID-19. As NPR reported. "In the Moderna study there were 30,000 volunteers. Half got two doses of the vaccine 28 days apart; half got two shots of a placebo on the same schedule. There were 95 instances of COVID-19 illness among the study participants; only five of those cases were in the vaccinated group. Ninety were in the group receiving the placebo." Injection Type No COVID (NC) COVID (C) Totals Placebo (P) 14.910 90 Vaccine (V) 14,995 5 Totals 1. State the null hypotheses 2. State the alternative hypotheses. 3. State what test should be used for this problem? 4. Why 5. Perform this test using all the steps listed above using $\alpha = .001$. Cell Observed Expected O-E $(O-E)^2$ PNC 14,910 VNC 14,995 PC VC 6. Degree of freedom 7. What is the $\chi^2$-crit? 8. What should Modema conclude? 9. Can we determine whether people who get the vaccine are less likely to get sick or not?
