It always good to see statisticians give a good hard kick to those who put the word “lies” into the saying “lies, damm lies, and statistics” … the politicians. In this particular case the Conservative Shadow Home Secretary Chris Grayling has been making comparisons between violent crime statistics from the 1990s and the year 2008/9 using the police recorded crimes statistics. The UK Statistics Authority has said (unfortunately it is a PDF document) something more or less along the lines of “you can’t do that” (in an astonished and shocked tone of voice).
According to the UK Statistics Authority, the method for recording crime statistics in police stations was standardised in 2002/3 leading to a marked increase in recorded crime that year due to the change. Indeed they point out that all published statistics on police recorded crime clearly emphasise the fact that the figures cannot be naively compared with values before 2002/3. The statisticians claim that crime figures should be obtained from the British Crime Survey.
The UK Statistics Authority is worried about politicians using statistics to mislead the public and discredit official statistics.
How does Chris respond ? Basically by saying that he doesn’t believe the BCS and that the increase in reported crimes are too big to be explained away by changes in the recording method.
Who would I rather believe ? Who would you rather believe ? A politician ? Or a statistician ? No contest really; statisticians may not have the best reputation, but at least they do not inspire the same level of disgust as a paedophile like politicians do.
The interesting thing is that people believe that violent crime has gotten worse over the last decade. As to why they believe this I don’t know, because from personal experience I can tell you that violent crime has decreased dramatically over the last decade. Back in the day, I used to be off down town most Saturday nights (and often Fridays too), and almost every night out there would be some sort of fracas varying from a bit of a scuffle in a pub, to an all out street brawl with police helmets flying. These days ? I tend to stay home a great deal more, and there is almost no violence that I can see around.
The whole reason for statistical surveys is to go beyond personal experience and belief, to get much closer to the truth. And when you have that statistical survey you do not throw it away because you do not like the results. You have to change your beliefs. Ordinary people can be forgiven for not doing so, but a politician in the position of Shadow Home Secretary has a responsibility to do his or her best for the country.
Let us examine the “lie” accusation a little closer. Using statistical data in an inappropriate manner such as comparing reported crime figures whose recording methodology was different, is just as much a lie as a school child yelling out “You smell”. It also helps to discredit statistics as a whole, because the public is given the impression that one set of statistics says one thing and another says another – which is not the case at all.
Hard for a Tory whose lies are told in the undoubtedly unselfish goal of removing the present Labour government.