Public transport stop selection to reduce the inequality in the distribution of accessibility

Overview & Synopsis

What-to methods for the design of Public Transport (PT) traditionally maximize overall efficiency. They do not generally embed the inequality of the distribution of accessibility into the optimization objective. However, such inequality is crucial, as it contributes to the car-dependency of areas underserved by PT. In fact, while inequality is generally considered in what-if methods, embedding it directly into a PT design optimization algorithm is challenging. We show here that this can be achieved by setting selected bottom quantiles of the accessibility distribution as objective function. For simplicity, we focus on the PT stop selection problem. With a heuristic algorithm, we compare the resulting equality-maximizing PT with conventional efficiency-maximizing PT. Our numerical results show that, already with the sole stop selection, inequality of accessibility is significantly reduced. This shows potential for even greater inequality reduction by applying our approach to other PT planning decisions.