{"id":65,"date":"2006-07-10T11:09:57","date_gmt":"2006-07-10T11:09:57","guid":{"rendered":"http:\/\/scientopia.org\/blogs\/goodmath\/2006\/07\/10\/lying-with-statistics-abortion-rates\/"},"modified":"2006-07-10T11:09:57","modified_gmt":"2006-07-10T11:09:57","slug":"lying-with-statistics-abortion-rates","status":"publish","type":"post","link":"http:\/\/www.goodmath.org\/blog\/2006\/07\/10\/lying-with-statistics-abortion-rates\/","title":{"rendered":"Lying with Statistics: Abortion Rates"},"content":{"rendered":"

Via [Feministe][feministe], we see a wingnut named Tim Worstall [trying to argue something about sexual education][worstall]. It’s not entirely clear just what the heck he thinks his argument is; he wants to argue that sexual education “doesn’t work”; his argument about this is based on abortion rates. This
\nis an absolutely *classic* example of how statistics are misused in political arguments. So let’s take a look, and see what’s wrong.
\n[feministe]: http:\/\/www.feministe.us\/blog\/archives\/2006\/07\/10\/lies-damn-lies-and-statistics\/
\n[worstall]: http:\/\/timworstall.typepad.com\/timworstall\/2006\/07\/sex_education_w.html#comment-19323490
\nHe quotes an article from the Telegraph, a UK newspaper. The telegraph article cites statistics from the UK department of health. Here’s what Worstall has to say:
\n>Yup, gotta hand it to them, the campaigners are right. Sex education obviously works<\/a>
\n>
\n>Abortions have reached record levels, and nearly a third of women who have an abortion have had one
\n>or more before.
\n>
\n>Department of Health statistics reveal that abortions in England and Wales rose by more than 700 in
\n>2005, from 185,713 in 2004 to 186,416.
\n>…
\n>Some 31 per cent of women had one or more previous abortions, a figure that rises to 43 per cent
\n>among black British women.
\n>
\n>The ever increasing amount of sex education, the ever easier provision of contraception is clearly >driving down the number of unwanted pregnancies.
\nClearly, Worstall and the author of the telegraph piece want us to believe that there’s a significant *increase* in the number of abortions in the UK; and that this indicates some problem with the idea of sex-ed.
\nSo what’s wrong with this picture?
\nFirst, let’s just look at those numbers, shall we? We’re talking about a year over year increase of *700* abortions from a base of *185,000*. How significant is that? Well, do the math: 0.37%. Yes, about one third of one percent. Statistically significant? Probably not. (Without knowing exactly how those numbers are gathered, including whether or not there’s a significant possibility of abortions being underreported, there’s no way to be absolutely sure, but 1\/3 of 1% from a population of 185,000 or so is not likely to be significant.)
\nBut it gets worse. Take a good look at those statistics: what do they measure? They’re a raw number of abortions. But what does that number actually mean? Statistics like that taken out of context are very uninformative. Let’s put them in context. From the [statistics for England and Wales][stats]:
\n[stats]: http:\/\/www.johnstonsarchive.net\/policy\/abortion\/ab-ukenglandwales.html
\nIn the year 2003, there were 621,469 live births, and 190,660 abortions. In 2004, there were 639,721 live births, and 194,179 abortions. Now, these stats from from the UK Office of National Statistics. Note that the numbers *do not match* the numbers cited earlier. In fact, taken as bare statistics, these numbers show a *much larger* increase in abortions: about 1.8%.
\nBut, put in context… Take the number of abortions as a percentage of non-miscarried pregnancies (which we need to do because the miscarriage statistics for the years 2003 and 2004 are not available), and we find that
\nthe number of abortions per 1000 pregnancies actually *declined* from 292\/1000 in 2003 to 290\/1000 in 2004. And that number from 2003 was a decline from 2002, which was a decline from 2001. So for the last four years for which statistics are available, the actual percentage of pregnancies ending in abortions has been nearly constant; but closely studying the numbers shows that the number has been *declining* for those four years.
\nIn fact, if we look at abortion statistics overall, what we find is that from the legalization of abortion in the UK, there was a consistent increase until about 1973 (when the number of abortions reached 167,000), and since then, the number has ranged upwards and downwards with no consistent pattern.
\nSo – what we’ve got here is a nut making an argument that’s trying to use statistics to justify his political stance. However, the *real* statistics, in context, don’t say what he wants them to say. So – as usual for a lying slimebag – he just selectively misquotes them to make it *look like* they say what he wants them to.<\/p>\n","protected":false},"excerpt":{"rendered":"

Via [Feministe][feministe], we see a wingnut named Tim Worstall [trying to argue something about sexual education][worstall]. It’s not entirely clear just what the heck he thinks his argument is; he wants to argue that sexual education “doesn’t work”; his argument about this is based on abortion rates. This is an absolutely *classic* example of how […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[51],"tags":[],"class_list":["post-65","post","type-post","status-publish","format-standard","hentry","category-politics"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p4lzZS-13","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"_links":{"self":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts\/65","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/comments?post=65"}],"version-history":[{"count":0,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/posts\/65\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/media?parent=65"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/categories?post=65"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.goodmath.org\/blog\/wp-json\/wp\/v2\/tags?post=65"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}