{"id":1294,"date":"2010-11-29T13:17:54","date_gmt":"2010-11-29T17:17:54","guid":{"rendered":"http:\/\/mat.tepper.cmu.edu\/blog\/?p=1294"},"modified":"2010-11-29T13:17:54","modified_gmt":"2010-11-29T17:17:54","slug":"everyone-needs-to-know-some-statistics-part-n1","status":"publish","type":"post","link":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/2010\/11\/29\/everyone-needs-to-know-some-statistics-part-n1\/","title":{"rendered":"Everyone Needs to Know Some Statistics Part n+1"},"content":{"rendered":"<p>I have previously written on how <a href=\"http:\/\/mat.tepper.cmu.edu\/blog\/?p=756\">decision makers<\/a> (and <a href=\"http:\/\/mat.tepper.cmu.edu\/blog\/?p=1107\">journalists<\/a>) need to know some elementary probability and statistics to prevent them from making horrendously terrible decisions.\u00a0 Coincidentally, Twitter&#8217;s <a href=\"http:\/\/twitter.com\/#!\/ORatWork\">@ORatWork<\/a> (<a href=\"http:\/\/john-poppelaars.blogspot.com\/\">John Poppelaars<\/a>) has provided a pointer to an excellent example of how easily organizations can get messed up on some very simple things.<\/p>\n<p>As reported by the blog <a href=\"http:\/\/www.badscience.net\/2010\/11\/1864\/\">Bad Science<\/a>, <a href=\"http:\/\/www.stonewall.org.uk\/\">Stonewall<\/a> (a UK-based lesbian, gay and bisexual charity) released a <a href=\"http:\/\/www.stonewall.org.uk\/media\/current_releases\/4867.asp\">report stating that the average coming out age has been dropping<\/a>.\u00a0 This was deemed a good enough source to get coverage in the <em><a href=\"http:\/\/www.guardian.co.uk\/world\/2010\/nov\/15\/gay-people-coming-out-younger-age\">Guardian<\/a>.<\/em> Let&#8217;s check out the evidence:<\/p>\n<blockquote><p>The average coming out age has fallen by over 20 years in Britain, according to Stonewall\u2019s latest online poll.<\/p>\n<p>The poll, which had 1,536 respondents, found that lesbian, gay and  bisexual people aged 60 and over came out at 37 on average. People aged  18 and under are coming out at 15 on average.<\/p><\/blockquote>\n<p>Oh dear!\u00a0 I guess the most obvious statement is that it would be truly astounding if people aged 18 and under had come out at age 37!\u00a0\u00a0\u00a0 Such a survey does not, and can not (based just on that question), answer any questions about the average coming out age.\u00a0 There is an obvious sampling bias:\u00a0 asking people who are 18 when they come out ignores gays, lesbians, and bisexuals who are 18 but come out at age 40!\u00a0 This survey question is practically guaranteed to show a decrease in coming out age, whether it is truly decreasing, staying the same, or even increasing.\u00a0 How both the charity and news organizations who report on this can&#8217;t see this immediately baffles me.<\/p>\n<p>But people collect statistics without considering whether the data address the question they have.\u00a0 They get nice reports, they pick out a few numbers, and the press release practically writes itself.\u00a0 And they publish and report nonsense.\u00a0 Bad Science discusses how the question &#8220;Are people coming out earlier&#8221; might be addressed.<\/p>\n<p>I spent this morning discussing the MBA curriculum for the Tepper School, with an emphasis on the content and timing of our quantitative, business analytics skills.\u00a0 This example goes to the top of my &#8220;If a student doesn&#8217;t get this without prodding, then the student should not get a Tepper MBA&#8221; list.<\/p>\n<p><strong>Added December 2.<\/strong> Best tweet I saw on this issue (from @sarumbear):<\/p>\n<blockquote>\n<div>\n<div><a title=\"#Stonewall\" rel=\"nofollow\" href=\"http:\/\/twitter.com\/#%21\/search?q=%23Stonewall\"><strong>#Stonewall<\/strong><\/a> &#8216;s survey has found that on average, as people get older, they get older. <a title=\"http:\/\/www.guardian.co.uk\/commentisfree\/2010\/nov\/27\/stonewall-gay-data-statistical\/\" rel=\"nofollow\" href=\"http:\/\/bit.ly\/gT731O\" target=\"_blank\">http:\/\/bit.ly\/gT731O<\/a> <a title=\"#fail\" rel=\"nofollow\" href=\"http:\/\/twitter.com\/#%21\/search?q=%23fail\">#fail<\/a><\/div>\n<\/div>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>I have previously written on how decision makers (and journalists) need to know some elementary probability and statistics to prevent them from making horrendously terrible decisions.\u00a0 Coincidentally, Twitter&#8217;s @ORatWork (John Poppelaars) has provided a pointer to an excellent example of how easily organizations can get messed up on some very simple things. As reported by &hellip; <a href=\"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/2010\/11\/29\/everyone-needs-to-know-some-statistics-part-n1\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Everyone Needs to Know Some Statistics Part n+1&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[15,39],"tags":[],"class_list":["post-1294","post","type-post","status-publish","format-standard","hentry","category-data-mining","category-or-in-the-press"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/posts\/1294","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/comments?post=1294"}],"version-history":[{"count":0,"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/posts\/1294\/revisions"}],"wp:attachment":[{"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/media?parent=1294"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/categories?post=1294"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mat.tepper.cmu.edu\/blog\/index.php\/wp-json\/wp\/v2\/tags?post=1294"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}