Value of Travel Time Savings. A study in the cross mode variations of mixed logit estimates.

The Value of Travel Time Savings (VTTS) is the monetary value attached to reductions in travel time. VTTS is an important willingness to pay (WTP) estimator which plays a crucial role in the evaluation of transport projects and pricing policies; it is often the case that travel time savings account for the biggest part of total monetized benefits in a transport project. Approximately four decades after the initial efforts to estimate VTTS, the indicator itself and its extensions remain in the centre of transport economists’ interest. One of these extensions is the large variations that characterize VTTS estimates across a plethora of factors. The scope of the thesis is to answer whether the observed cross transport mode variations in the estimates are mainly due to one broad family of factors, namely the user type effects (socioeconomic variables such as income, gender etc.), or due to a second family of factors that consist the mode effects (attributes of the mode such as speed, safety and comfort). A third theoretical possibility is that the differences stem from the strategic behavior of the respondents (the agents escape the context of the experiment and perceive incentives to not reveal their true WTP) in the choice experiments (CE). The origin of VTTS variations is a rather critical question, especially when it comes to complicated transport projects which involve simultaneous changes in the market shares and in WTP of the travelers in a given transport mode. What is investigated is rather the relative power of these effects than the dominance of one of them; therefore, we admit an ex-ante coexistence of at least user type and mode effects rather than checking for a polar case. Our focus is on the relative power of the two effects which is responsible for the change in total monetized benefits. The empirical results of the study can be grouped in two parts. In the first one, re-estimation of VTTS with mixed logit from Norwegian SP data takes place. The estimations involve experimentation with various mixing distributions. The result is a variety of estimates which enrich the empirical findings of the Norwegian Value of Time (VoT) study in 1997. In addition, models which control for income and gender are developed, allowing for socioeconomic segmentation of VTTS. The second part, which answers the central question, adopts the model with Normal mixing distribution and exploits the experimental design of the study in order to separate the effects from each other. Then, practical LR tests are employed to check for the significance of the observed differences in VTTS. The concluding remarks pose future challenges which arise from the complex nature of the issue

The effects of transport infrastructure on regional economic development: A simulated spatial overlapping generations model with heterogenous skill

JTLU vol 5, no 2, pp 77-101 (2012)As a result of public investment, lower freight transport costs tend to translate into lower local price indices and are associated with equilibria characterized by higher output and consumption. In this paper we investigate an additional effect to these trade gains, namely the gains from better spatial matching in the labor market. We simulate a two-region Spatial OLG model in which agents are heterogeneous in terms of skill. Under repeated simulation experiments, we show that, for high household relocation frictions, the possibility of interregional commuting can be seen as an alternative way to realize the potential matching effects. For high levels of skill heterogeneity and a plausible parametric input, a steady state in which labor matching is realized through commuting can be associated with up to 10% higher per capita output, compared to the one with homogenous labor, in which only gains from trade are feasible

Essays on regional labor markets: interactions with land and transport.

QC 201102

Spin-off : Individual, Firm, Industry and Regional Determinants

The extent and importance of spin-offs for industrial dynamics have been analysed in a number of previous studies, yet knowledge is surprisingly scarce about the determinants that trigger such entrepreneurial ventures. In the current analysis we use unique and detailed Swedish data to comprehensively explore how individual, firm, regional, and industry variables influence spin-offs during 1999-2005. In addition to the expected general positive impact of regional size and entrepreneurial culture, we find specific features for knowledge intensive manufacturing and service production on the propensity of employees to spin off a new venture. Moreover, we use an entropy measure to disentangle unrelated and related variety, and find that the former has a significantly negative impact while the latter a significantly positive effect on the propensity of the individual to start a spin-off.QC 2012050

Spin-offs: Why geography matters

Based on unique data covering individuals, firms, industries and regions for the 1999-2005 period, we contribute with new knowledge concerning the impact of regional variables on spin-offs. Implementing a large number of controls, as well as different estimation techniques and robustness tests, we show that Jacobian externalities have a positive effect on spin-offs. Moreover, using an entropy measure to disentangle unrelated and related variety (RV), we conclude that the effect is confined to RV. These findings are likely to be associated with strong welfare effects: a standard deviation increase (decrease) in related (unrelated) variety increases spin-off propensity by approximately 25%. Other variables are shown to have economic effects of a similar magnitude but may have a different effect across sectors. Sensitivity analyses indicate that the impact of other determinants proposed in the literature (e.g., Marshallian externalities and scale effects) is too small to be detected

Second-best urban tolls in a monocentric city with housing market regulations

This paper investigates second-best congestion pricing in a monocentric city characterized by distortionary regulations in the housing market (building height restrictions, no-development areas and property taxation). We demonstrate that the welfare gain of a Pigouvian tax may first fall and then increase as building height restrictions become more stringent. For example, a Pigouvian toll imposed in a city without restrictions may produce up to 40% larger welfare gains than Pigouvian tolling in a city with a mild, uniform in space, floor-to-area ratio restriction. In the presence of a tax-induced distortion, deviations of the Pigouvian toll can lead to non-negligible welfare gains. We discuss the important policy implications of the above findings