Estimating the effect of accessibility on wages

In this paper, we estimate the elasticity of wages in Denmark with respect to changes in generalised travel costs. The estimation of the elasticity is done on Danish register data from year 2002 and 2010. This elasticity is used as an estimate for the productivity effects of transport infrastructure changes and is to be applied in calculations of the wider economic benefits of transport infrastructure improvements in Denmark.&nbsp

Analyse af rejsetidsvariabilitet på danske motorveje

Variabilitet i rejsetider, som betyder at det er vanskeligt at forudsige hvor lang tid en tur tager, er en negativ konsekvens af bl.a. trængsel og hændelser på vejene. I samfundsøkonomiske analyser håndteres det i dag ved, at tidsværdien af forsinkelser er højere end tidsværdien for almindelige rejsetid. Denne metode er dog ikke altid tilfredsstillende, og grundlaget er forholdsvis svagt dokumenteret. Transport DTU og Vejdirektoratet har forsøgt at anvende GPS-data til at kortlægge sammenhængen mellem forsinkelse og variabilitet, for at undersøge om det er muligt at forudsige rejsetidsvariabilitet ud fra forsinkelser. Hvis det er muligt, vil man kunne forudsige ændringer i rejsetidsvariabilitet ud fra output fra trafikmodeller, og variabilitet vil dermed kunne værdisættes mere direkte i den samfundsøkonomiske analyse. Resultaterne af denne analyse viser en tydelig sammenhæng mellem forsinkelse og variabilitet, hvilket betyder, at det måske er muligt at opstille en simpel efterberegningsmodel til LTM, der beregner ændringer i rejsetidsvariabilitet som følge af transport- og infrastrukturprojekter. I forbindelse med analysen er det dog tydeligt, at der er behov for videreudvikling af metoden, før den implementeres i den samfundsøkonomiske analyse

Travel time variability:Definition and valuation

Increasing traffic leads to increasing severity, spatial extension and duration of congestion. Congestion has two immediate consequences. One is that travel times increase on average. Another is that travel times become increasingly variable and unpredictable. When performing economic appraisal of transport policies it is important to account for both. This is fast becoming widely acknowledged in many countries around the world. The subject is, however, quite difficult for several reasons and so far there is no established consensus on how to define and value travel time variability. This report was commissioned by the Danish Ministry of Transport and its agencies Vejdirektoratet (the Road Directorate) and Trafikstyrelsen (the Rail Agency). Its purpose is to establish a definition of travel time variability and its value that is theoretically sound, possible to estimate from individual preferences, and applicable with existing or realistically foreseeable traffic models. In addition, the report provides short term recommenda- tions for including valuation of travel time variability in Danish practice for economic appraisal of transport projects and outlines a future Danish study of the valuation of travel time variability