Final Review

1. Final Review Type I, Type II errors and Power of a Test

2. Final Review Pentagon Sees Little Risk in Allowing Gay Men and Women to Serve Openly – NYT, Nov. 30, 2010 The Pentagon has concluded that allowing gay men and women to serve openly in the United States armed forces presents a low risk to the military’s effectiveness, even at a time of war, and that 70 percent of surveyed service members believe that the impact on their units would be positive, mixed or of no consequence at all. In an exhaustive nine-month study on the effects of repealing “don’t ask, don’t tell,” the 17-year-old policy that requires gay service members to keep their sexual orientation secret or face discharge, the authors concluded that repeal would in the short run most likely bring about “some limited and isolated disruption to unit cohesion and retention.” But they said those effects could be mitigated by effective leadership. The report, by Jeh C. Johnson, the Pentagon’s chief legal counsel, and Gen. Carter F. Ham, the commander of the United States Army in Europe, also found that much of the concern in the armed forces about openly gay service members was driven by misperceptions and stereotypes. Leaving aside those with moral and religious objections to homosexuality, the authors said the concerns were “exaggerated and not consistent with the reported experiences of many service members.” …….. Mr. Obama, who campaigned for president on a promise to repeal the law, hailed the study. “Today’s report confirms that a strong majority of our military men and women and their families — more than two-thirds — are prepared to serve alongside Americans who are openly gay and lesbian,” he said in a statement. - link to article

3. Final Review

4. Final Review Service member sample size. The Service member sample population included 199,962 Active Duty Service members and 199,894 Reserve and National Guard members. Survey administration for the Service member survey began on July 7,2010, and continued through August 15, 2010. Five reminder notices were sent to Service member nonrespondents, with two of the notices sent by both email and postal mail and the other three by email only. In addition, the individual Services independently sent communications encouraging participation in the survey to their Service members. The Defense Manpower Data Center (DMDC) developed the sample design and provided it to Westat for review. DMDC used data from its personnel files to create sampling frame strata. DMDC selected the samples from the frames and updated the sample files for both surveys just prior to administration. The process of weighting refers to the calculation of a sampling weight for each survey respondent. Weighting is appropriate when the sample design is complex (that is, sample members do not all have the same probability of selection) and there is nonresponse to the survey Statisticians adjusted the weights to take into account differences in response rates across demographic categories. The Service member survey had an overall weighted response rate of 28%. Link to study

5. Final Review “Finding the occasional straw of truth awash in a great ocean of confusion and bamboozle requires intelligence, vigilance, dedication and courage. But if we don't practice these tough habits of thought, we cannot hope to solve the truly serious problems that face us and we risk becoming a nation of suckers, up for grabs by the next charlatan that comes along.” —Carl Sagan(1934-1996), Astrophysicist and advocator of skeptical inquiry