Britain’s public health boffins have got the government agitated enough to try major incentives to encourage British shoppers to buy healthier, lower-calorie foods. Tim Worstall explains that, because those shoppers are human beings, this suite of incentives won’t do at all what Nanny expects them to do:
Now consider how it has to work. You go shopping, you present your DimbleCard and gain points for the healthiness of that shopping basket. Lettuce and carrots galore, super, free ticket to London on the choo choo.
So, where are the chocco biccies? If you buy them when presenting your card then no choo choo for you. What happens?
The lettuce and the carrots are bought on the card, the chocco biccies are not. Everyone simply does two transactions, with DimbleCard and sans. Lots of free choo choo and no change, whatsoever, in diet.
Yes, of course people will do this. For that’s what people do. Survey the landscape of incentives in front of them then maximise their utility, the outcome, in the face of them. It’s a restricted rationality, restricted by knowledge, but it is there. Everyone will fiddle the system because that’s what it is to be human. Collecting the fire from the lightning strike is fiddling the universe, that’s just what we do.
This being why so many clever schemes to encourage or deter this or that just don’t work. This being why those detailed plans for men, if not mice, gang aft into idiocy. Because we out here, hom sap, will play whatever system there is to our benefit.
No, this will not work out like supermarket loyalty cards. Yes, it’s true, most of us do use them. But the incentive is for us to do so. The more we do use them then the more discounts we gain, the better off we are, even at the cost of that data. How does this new government one work? The less we buy of certain things the better off we are. So, less of those things will be bought using the cards.
It is not possible to insist that people must use the card to buy things. Well, not unless we’re about to descend into the dystopia desired by Caroline Lucas it’s not. There might be a card reader at the point of purchase but the supermarkets will not demand that a sale can only happen when a card is read.
Therefore there will be those sales which gain points which make prizes. There will also be those DimbleCardless sales which do not gain points, or even demerits, and are done without their being registered in the system.
