I have just started reading a classic book on how we think: Irrationality by Stuart Sutherland. It is 20 years old but has been reissued. As the title suggests it is about how we (all of us) routinely think and make decisions in a pretty dumb way. One of the most commons ways we mess up is due to what is called ‘availability error’. We make decisions based on the most immediate and striking facts available to us, the ones in the forefront of our minds. These striking facts are often unreliable and unrepresentative.
For example, psychologists gave people a list of names, half of which were men and half of which were women. First they used a list in which many of the men were famous, Winston Churchill etc, but none of the women. The psychologists then asked: “Did the list contain more male names than female names, or the other way around?”. Most responded: more male. They gave a second lot of people a second list with again 50% male names and 50% female names, but now the women were famous. This time people thought there were more women than men on the list.
This is the availability error, making decisions based on the impressions in the forefront of our mind, here the famous people, not based on simply trying to count names ignoring whether we had heard of them – which was irrelevant here as the people were just asked for whether they were male or female names not whether they were famous or not.
So we as a species are prone to thinking in this clearly very far from optimal way. Because of this weakness, stories like this one in The Daily Mail about families on benefits with seven children, a plasma tv and a Mercedes, are a bit of a worry. The rational way for taxpayers like you and me to think about benefits for families would be on the basis of what typical families receive in terms of benefits, why they qualify to receive them, and what they spend the money on. It is these typical families that are receiving most of our money. But if we are not careful, we can easily fall into this trap of making judgments based on the most available evidence, not the most reliable, and frankly some newspapers are not helping here.
Chance & Necessity 