There is a wonderful book called "How to Lie with Statistics" by Darrell Huff and Irving Geis.
A very real-world example of this was discovered by Eric at Classical Values:
bq. More murder is less!
Bill Barnes, described as the principal architect (via Jeff Soyer) of the proposed ordinance to ban handguns in San Francisco, is a man destined to go far in politics. Consider this dazzling display of statistical talent in his discussion of the District of Columbia gun ban in the San Francisco Bay Guardian:
Meaningful gun reform is one part of making communities safer. New investments in education, community development, and jobs are also needed to provide real alternatives to violence. Nevertheless, fewer handguns in the flow of commerce will make it more difficult to obtain one. A community conversation about the violence caused by handguns will lift our city up, as neighbors talk to one another about strategies to increase the peace in our neighborhoods.
bq. Once you get past the "community conversation," be sure to read and parse what follows very carefully, and keep a close eye on the moving number "20." Note the clever way "20-year low" (which is not there yet, but is "on its way') follows "more than 20 years ago." That's the sort of manipulation that experienced store owners (conned one time too many into refunding too much change) would spot, but I'm afraid most Bay Areans -- especially those who agree with the gun ban -- missed it. bq. While I'm sure very few of San Francisco's gullible read this blog, I do think it's fair to point out that "more than 20-years ago" means 1976! (That's almost thirty years ago!) bq. What Mr. Barnes does not tell you is that the murder rate had been dropping before the ban. And in the time period since the ban, the District's murder rate and robbery rate have gone up, and, with the exception of one year, remained consistently higher:More than 20 years ago, the District of Columbia enacted a similar handgun ban and is on its way to a 20-year low of homicides. Yet Republicans in Washington are working to repeal the law. (Emphasis supplied.)
....with a murder rate of 46 per 100,000 people in 2002, the District easily holds the title of the U.S. murder capital among cities with over 500,000 people. This was not even close to being the case prior to the ban.
bq. So actually, DC gun ban statistics are a persuasive argument against the San Francisco ordinance; not the other way around. (As recently as 2002, Washington earned the title of "the Nation's Murder Capital.") bq. I have to admit, Barnes has balls. Not every political strategist can turn an argument against something into an argument for it. bq. Of course, as Michael Bellesiles proved, it works better if you simply falsify the data. Barnes is sooo busted. Fact checking is a wonderful thing to do and Eric displays a masters touch... In the SF Bay Guardian Op-Ed, Barnes also voices this tired old canard: bq. According to data collected by the Centers for Disease Control and Prevention, firearms are the second leading cause of death for kids 19 and younger. Yeah -- and the majority of those deaths are in the 16 to 19 age group and are inner-city gang related. If you drop the age group of your "children" to a more reasonable 0 to 12, the instance of gun violence drops off the charts. Banning handguns will not prevent criminals from getting them and being able to get them easily.Crime rose significantly after the gun ban went into effect. In the five years before Washington's ban in 1976, the murder rate fell from 37 to 27 per 100,000. In the five years after it went into effect, the murder rate rose back up to 35. During this same time, robberies fell from 1,514 to 1,003 per 100,000 and then rose by over 63 percent, up to 1,635. The five-year trends are not some aberration. In fact, while murder rates have varied over time, during the almost 30 years since the ban, the murder rate has only once fallen below what it was in 1976.
