An alternative conception of consumer choice has recently gained the attention of economists, which allows for two closely related departures from the standard model. First, consumers may have dynamically inconsistent preferences. Second, as a rational response to this dynamic inconsistency, the consumer may use external commitment devices or personal rules in an attempt to limit overspending. We use data from a large, representative sample of households in the UK to test the relevance of these twin predictions in the field. We find evidence that consumption spending declines between paydays, and jumps back to its initial level on the next payday. The decline is too steep to be explained.
