Herding and the quest for credit

The system for awarding credit in science – the ‘priority rule’ – functions, I have proposed elsewhere, to bring about something close to a socially optimal distribution of scientists among scientific research programs. If all goes well, then, potentially fruitful new ideas will be explored, unpromising ideas will be ignored and fashionable but oversubscribed ideas will be deprived of further resources. Against this optimistic background, the present paper investigates the ways in which things might not go so well, that is, ways in which the priority rule might fail to realize its full potential as an incentive for scientists to work on the right things. Several possible causes of ‘herding’ – an outcome in which a single research program ends up with a number of researchers well in excess of the optimum – are considered.