Heuristic algorithms for a second-best congestion pricing problem

Designing a congestion pricing scheme involves a number of complex decisions. Focusing on the quantitative parts of a congestion pricing system with link tolls, the problem involves finding the number of toll links, the link toll locations and their corresponding toll level and schedule. In this paper, we develop and evaluate methods for finding the most efficient design for a congestion pricing scheme in a road network model with elastic demand. The design efficiency is measured by the net social surplus, which is computed as the difference between the social surplus and the collection costs (i.e. setup and operational costs) of the congestion pricing system. The problem of finding such a scheme is stated as a combinatorial bi-level optimization problem. At the upper level, we maximize the net social surplus and at the lower level we solve a user equilibrium problem with elastic demand, given the toll locations and toll levels, to simulate the user response. We modify a known heuristic procedure for finding the optimal locations and toll levels given a fixed number of tolls to locate, to find the optimal number of toll facilities as well. A new heuristic procedure, based on repeated solutions of a continuous approximation of the combinatorial problem is also presented. Numerical results for two small test networks are presented. Both methods perform satisfactorily on the two networks. Comparing the two methods, we find that the continuous approximation procedure is the one which shows the best results.     

Industrial clusters,flagship enterprises and regional innovation

ABSTRACT

For a sample of all 88 counties in the State of Ohio over a 5-year period, this study documents the effect of flagship enterprises and concentrated industrial clusters on regional innovation. Consistent with the agglomeration arguments and the knowledge spillover theory of entrepreneurship, both appear to affect regional innovation positively. Additionally, regional educational attainment positively moderates the effect of industrial clusters on innovation. At the same time, flagship enterprises primarily affect regional innovation in regions with low education levels. Results are obtained with the help of conservative econometric techniques and are robust to the choice of alternative dependent variables and estimators. The findings have major policy implications and provide insights into alternative routes to encouraging regional innovation.     

Panel cointegration and the monetary exchange rate model

This paper re-examines the validity of the monetary exchange rate model during the post-Bretton Woods era for 18 OECD countries. Our analysis simultaneously considers the presence of both cross-sectional dependence and multiple structural breaks, which have not received much attention in previous studies of the monetary model. The empirical results indicate that the monetary model emerges only when the presence of structural breaks and cross-country dependence has been taken into account. Evidence is also provided suggesting that the breaks in the monetary model can be derived from the underlying purchasing power parity relation.     

Implementation intentions in the entrepreneurial process: concept,empirical findings,and research agenda

Prior studies find sizable gaps between entrepreneurial intentions and subsequent actions. We extend models of entrepreneurial intentions by drawing on action phase theory to better understand how entrepreneurial intentions translate into actions. Our study focuses on the effects of implementation intentions on taking entrepreneurial action. The analysis uses two waves of survey data on 422 individuals, from the Swedish general population, who had an explicit interest in starting a business and who reported on their actions 6 months later. We test and find support for a moderated mediation model in which implementation intentions mediate the effects of goal intentions on taking entrepreneurial action. We further find the mediated effect to be even stronger for those confirming a strong intention to start a new business. We provide an in-depth discussion of the concept of implementation intention and an extensive research agenda.     

Industry Dynamics in the Swedish Textile and Wearing Apparel Sector

This paper analyses the adjustment process within the Swedish textile and wearing apparel sector and finds results that support the notion of Schumpeters creative destruction. The turnover of plants and jobs seems to improve the industries from within due to an exit (entry) of less (more) productive plants, exit (entry) of old (new) incumbents, a destruction (creation) of less (more) human-capital intensive jobs, and a supply of new products on the world market. The econometric analysis of the probability of exit with plant, firm and industry characteristics supports the idea of a rationalisation from within.