My young children, aged five and eight, are driving me insane. I try to discipline them, but they can be so wilful. At times I lose my temper and spank them. Is this wrong?

What else can I try?

Yours,

Gill Harnsley, Chelsea

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Dear Ms Harnsley,

Children are rational utility maximisers, but they have a high discount rate and therefore a short time horizon. Small immediate punishments and rewards are the most efficient way to give them the right incentives to behave.

Parents have trouble making credible promises of future punishments. Rational children know they can ignore threats of punishment if you have a record of bluster.

These two facts together argue for the time-honoured tradition of a chart with stars and black marks. The immediacy of the reward or punishment outweighs the fact that it is, after all, just a mark on a bit of paper. The chart can be reinforced by tying pocket money to the number of stars minus the number of black marks. This is an objective, transparent policy framework that will make it harder for you to renege on your threats: if the black marks are there on the chart, you can hardly cough up the allowance at the end of the week.

There is no need to spank your children unless you are poor. This is not to hold poor parents to different standards, simply to recognise that if a family is not rich enough to pay a generous allowance, then there is no financial threat available. The main alternative to withdrawing pocket money is spanking, which is free.

The economist Bruce Weinberg has found that very poor parents spank their children and withdraw allowances less frequently than other parents, even those of modest income. But if you can afford reasonable pocket money, then taking it away is all the punishment you need.

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