What Could Lifestyle Appraisal Look Like in Practice and Can It Potentially Improve Current Appraisal?
Peter Davidson, Peter Davidson Consultancy, Helen Porter, Peter Davidson Consultancy, Oliver Capon, Peter Davidson Consultancy
This paper outlines appraisal with lifestyle models, illustrates some deficiencies with current appraisal methods and shows how lifestyle models could offer the prospect of helping to ameliorate some of them.
Lifestyle models are described in another abstract, so this paper develops ideas for the appraisal methodology which could be adopted. The idea is that over time people take every opportunity to improve their lifestyle and this could perhaps be quantified so government policy, transport schemes and initiatives can if necessary be orientated to improve people’s lifestyle over time.The lifestyle model would be focussed on the household individual so as to model the accumulation of lifestyle improvements people make over time when they get a better job with more income, perhaps closer to home or when they move to a better house or school with better job prospects for their children or when they move to the countryside (or into the city) to be happier or when the home-minder gets a job (or gives up their job to be with the children). All these individual lifestyle improvements could potentially accumulate to an additional benefit.
Lifestyle models are built upon a conventional activity based model so the conventional appraisal methodologies can be used by switching the lifestyle component off. However the lifestyle component could improve appraisal. Lifestyle models add two new quantities: a quantification of the value of the activity being performed at the destination and a quantification of the additional lifestyle improvements that could accrue to people due to the scheme offering them a better quality of life.
Undertaking an activity has a value which is greater than the disutility of getting there (otherwise people would not do it) so the benefit of undertaking the activity is greater that the dis-benefit of getting there.Including the change in the value of the activity into the appraisal is not a new idea as conventional appraisal considers that it is the same in both the Do Nothing and the Do Something scenarios. However if the activity pattern does change then this change is a potential benefit (otherwise the person would not have changed) which could potentially be included in the appraisal process, provided it can be measured.
For example, one recent problem for appraisal is the empirical evidence that the value of train in-vehicle time for appraisal seems to be affected by the use the traveller makes of his time – particularly doing work or using a computer or emailing or having meetings. Recent studies have successfully measured this value of activity time (Wardman). We postulate that this on-train activity may also affect the activity undertaken at the destination. For example if a person can respond to all his emails on the train before he gets into the office, his office activity could be different than if he travelled to work by car where he cannot email. We postulate that including the value of the activities in appraisal could offer a way forward to address such issues.
Another example is appraising traffic calming schemes which are designed to restrict vehicles in a residential area, displacing them onto the neighbouring roads, increasing travel times, thereby causing a dis-benefit. This is counter-intuitive because, despite its considerable cost, the scheme is considered to be beneficial overall (or it would not be implemented). We postulate that the traffic calming scheme has produced a better lifestyle for its inhabitants which outweighs the dis-benefits of the scheme cost and the congestion caused. Including this lifestyle component into the appraisal process could be a way of addressing this appraisal difficulty.
These illustrate the principle of lifestyle appraisal which the paper will develop in more detail putting the flesh on the bones developed during the recent ETC discussions. The innovation is in the development of the lifestyle appraisal into a practical model architecture which we postulate in the paper.
Association for European Transport