PhD defence of Twan Dollevoet on Thursday 10 January 2013

Promotie Twan Dollevoet op donderdag 10 januari 2013

On Thursday 10 January 2013 Twan Dollevoet will defend his PhD thesis entitled 'Delay Management and Dispatching in Railways'. Supervisor is Professor Albert Wagelmans and co-supervisor is Dennis Huisman. Other members of the Doctoral Committee are Professor Leo Kroon (Erasmus University Rotterdam), Professor Anita Schöbel (University of Göttingen) and Dario Pacciarelli (Roma Tre University).

Time and location

The PhD defence will take place in the Senate Hall of Erasmus University Rotterdam and will start at 13.30 hrs.

About the dissertation

Passenger satisfaction has become an important performance indicator for passenger railway operators. One of the key aspects for passenger satisfaction is the reliability of transfers between trains. When a train arrives at the station with a delay, travellers might miss their connection if the next train departs on time. Although these passengers prefer the connecting train to wait, this introduces delays for many other passengers.

In his PhD dissertation entitled Delay Management and Dispatching Railways, Twan Dollevoet develops models and solution methods to compute wait-depart decisions (i.e. whether the connecting train should wait for delayed transfer passengers or depart on time) with the aim of minimising the total delay. In cooperation with Netherlands Railways (NS), he tests his methods on instances and shows that delay for passengers can indeed be reduced.

Twan Dollevoet emphasises: "If more transfers are maintained during the operations, the passengers' arrival times at their destinations will be more reliable. As a consequence, more people might choose to travel by train."

About Twan Dollevoet

Twan Dollevoet holds master's degrees in Mathematics and in Physics from Utrecht University and in Econometrics and Management Science from Erasmus University Rotterdam. In 2008, he started his PhD research at the Erasmus School of Economics. His main research interest is in Operations Research, and in particular in applications of combinatorial optimisation, such as railway scheduling, inventory control, and route planning for unmanned aerial vehicles. Simultaneously with his PhD research, Twan has worked as a researcher at the department Process Quality & Innovation of Netherlands Railways. At Netherlands Railways he has mainly worked on crew scheduling.

The research described in his thesis has been presented at various conferences, such as TRISTAN, EURO, the INFORMS Annual Meeting, IFORS, and CASPT. The second chapter of his thesis has been published in Transportation Science. For this chapter, Twan and Marie Schmidt were awarded the first prize in the 2010 Student Research Paper Contest in the Railroad Application Section of INFORMS. The prize was presented at the 2010 Annual Meeting in Austin, Texas. Papers based on the other chapters have been submitted to Transportation Science, Public Transport, and Flexible Services and Manufacturing. Furthermore, a paper on crew scheduling has been published in Public Transport, and papers on mission planning and inventory control have been submitted to Annals of Operations Research and IIE Transactions, respectively. From January 2013, Twan will work as an assistant professor at the Econometric Institute of Erasmus University Rotterdam. He will continue to work on real-time railway scheduling within the European project ON-TIME.

Abstract of Macroeconomic Perspectives on the Equity Premium Puzzle

This dissertation deals with the equity premium puzzle, taking a macroeconomic perspective. It first develops a method to quantify the uncertainty surrounding estimates of risk aversion showing that the confidence bands surrounding these estimates are generally wide. The second chapter introduces a heterogeneous agent model populated by stockholders and nonstockholders that shows that risk aversion estimates of stockholders are lower than those based on a single representative agent. An aspect of the standard analysis that has received little attention is the risk-free rate. This dissertation argues that some kind of return on a savings account (or time deposit) is much closer to the "asset reality" a household is faced with than the widely used 3-month T-bill rate. To show the variability in risk aversion over time, the final chapter formulates an asset pricing model in which risk aversion varies in response to news in consumption growth, inflation and unemployment growth. Risk aversion is estimated to be highly persistent and, as expected, in the run-up to recessions and during these periods it is generally rising.

More information

Dollevoet’s PhD research project is conducted within the Erasmus Doctoral Programme in Business & Management, organised by Erasmus Research Institute of Management (ERIM), the joint research institute of Rotterdam School of Management, Erasmus University (RSM) and the Erasmus School of Economics (ESE) at Erasmus University Rotterdam.

For more information about this ceremony, please contact Ronald de Groot, Communication Officer of the Erasmus School of Economics phone +31 10 408 1762 or by e-mail: