Four kinds of bias

Four kinds of bias

30 May 2016

1)      SELECTIVE USE OF FACTS It is not news to say that people will select facts and opinions that appear to favour their side of an argument. There was a good example last week from the pro-Remain CBI which wants to demonstrate that the possibility of Brexit is already hurting investment. “Overall, surveys of investment intentions have shown a deterioration in investment plans, particularly in the services sector. Some of this is likely to be related to uncertainty ahead of the EU referendum. Although our April investment intentions data for the manufacturing industry actually strengthened, anecdote from the sector suggests some specific factors at play – in particular, replacement spending in the food & drink sector (following flood-related damage earlier in the year) and buildings investment by chemicals manufacturers looking to expand production on the back of solid export demand.” CBI Economic Forecast 16th May 2016 Did you get that? The latest data suggest that their view is wrong so they have concluded that the data are wrong. The CBI is supposedly a highly respectable organisation (so respectable that the EC contributes money to fund some of its publications) and can get away with substituting anecdote for data, or so it seems.    The Leave side is mostly less respectable and, partly by virtue of the necessity that it is promoting something of a leap in the dark, rarely seems to attempt to employ hard facts. But you can be sure that it is highly selective in what it says. You would imagine that the UK is full of people who are deeply worried about immigration. According to a survey that goes back to 1962, the peak year for UK citizens thinking that there are too many immigrants was 1970 when the level reached 89%. In 2014 it was 54%. Enoch Powell’s infamous “rivers of blood” speech was made in 1968 and probably contributed to the high level of antipathy to immigration that the chart shows. During the speech, Powell quoted a white constituent (in Wolverhampton) as saying: “In this country in 15 or 20 years’ time the black man will have the whip hand over the white man.” As it happened, the period...