Mobility through manipualtion

Caspar Chorus: “People make choices to minimize their regret”

The government is shifting its focus from facilitating mobility to managing mobility, says Caspar Chorus. His ‘regret model’ helps predict how your transportation choices will be influenced in the future.

Until about fifteen years ago, the government believed in building more roads as a solution to the issue of mobility,’ says the newly appointed Antoni van Leeuwenhoek Professor, Caspar Chorus (TPM). ‘Now the question is how many cars and motorways do we really want and how can we use the existing infrastructure as effectively as possible. The government made funding available for travel information, extra rush-hour lanes, and tax incentives. I think that the more the government seeks to influence road users, and the more subtly it does so, the more valuable our regret model becomes.’

Chorus is sitting behind his empty desk in the TPM building. Behind him hangs a 65-year-old academic gown with his name in it. His grandfather wore it when he was a professor of psychology in Leiden. The ‘regret model’ that Chorus Jr. has developed combines psychology with econometrics in the field of mobility, but it seems that it could be applied to all kinds of behaviour, including that of people on dating sites for example. The regret model is an alternative to the utility model, which economists have traditionally used to explain consumer choices. When buying a house for example, someone will look at location, maintenance, neighbourhood, price etc., and will process all this in his head to arrive at a total personal utility value. According to economists, this assessment of utility is independent of any houses for sale down the road.

In the late 1950s an alternative idea of behaviour was put forward: people also allow themselves to be guided by what they do not choose, when making their decision. They weigh the price of a lottery ticket against the possible regret of not having bought one. The postcodeloterij makes use of this by dividing its prize money over a whole street – that is, the people in that street who bought a ticket. Who would risk becoming the laughing stock of the neighbourhood? Chorus has translated this idea into an econometric model, and in doing so he has built a bridge between psychologists – who take a mainly qualitative view – and economists – with their penchant for mathematics.

People make choices to minimise their regret, says Chorus. Hence many people end up with a compromise. Maximising utility or minimising regret – it may all sound like much of a muchness, but the essential difference is that the regret model incorporates alternative choices. The introduction of this type of behavioural mechanism into the model leads to better predictions of mobility decisions, especially when it comes to the type of subtle influence that the Behavioural Insight Team (BIT) of the Ministry of Infrastructure and Environment has been eagerly awaiting.

The provision of information plays an important role in influencing people. This is already the case when the government and transporters such as the Dutch Railways suggest alternative routes in the event of line closures, also indicating the additional travel time. According to the regret model, certain alternative routes can be made more attractive by mentioning them alongside selected other routes. So when a range of alternatives are presented, it is possible to influence the choices made by passengers. The Regret Model can be used to calculate these effects.

‘The subtle manipulation of traveller might seem very futuristic,’ Chorus says, ‘but experiments are already being done whereby people are provided with very personal and rich travel information, which affects their behaviour in terms of their choice of transport and route.’

Previously, traffic models were static and calculated traffic flow projection over ten years. These days they are online, real-time, and they take account of the changes that they set in motion themselves. Mobility, and with it traveller behaviour, has itself become dynamic.

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