Accessibility has for many years been a widely used tool in transportation research. Many definitions have been suggested and researchers have constructed numerous mathematical formulations to measure its value in order to be able to evaluate the relationships between the nature of the transport systems and the patterns of land use. Such correlations have been used especially in assessing existing transport systems and forecasting their performance to provide decision-makers with ideas about the need for investments in the transport systems. However, accessibility measures can be regarded as the spatial counterparts of discounting. The measures represent the spatial distribution of economic agents and their activities in a simple way that imposes a very clear structure upon the relationship between these agents and their activities and their environment. Various frictional effects arising from geographical distance between economic agents determine their interaction options, that is, their options to trade, to cooperate, to learn, to commute, and so on. Observing that the time sensitivities of the economic agents vary between different spatial scales (and between different economic activities) we may impose a spatial structure (for example, local, intra-regional, interregional and international) which offers opportunities to define variables in such a way that spatial dependencies can be accommodated. These newly defined variables can then be used in empirical explanations of various spatial phenomena, such as patent output, new firm formation, the emergence of new export products, and economic growth in different spatial units. We will in this chapter against this background show that accessibility is an underused analytical and empirical tool in regional science with an underestimated potential.

Developed countries must be incredibly innovative to secure incomes and welfare so that they may successfully compete against international rivals. This book focuses on two specific but interrelated aspects of innovation by incumbent firms and entrepreneurs, the role of geography and of open innovation.

The rapid developments in information and communication technologies (ICT) and the increased use of ICT motivate the vision of an evolving digital economy. During the last decade this evolving digital economy has been the pre-eminent driver of structural change and economic growth at both the national and the regional level in the developed, industrialised economies. The reason is, of course, that ICT functions as a new generic technology, which impacts society both broadly and deeply. ICT has, in essence, destabilised the near equilibrium conditions of an earlier time and contributed to conditions of greater disequilibrium. Thus, one major implication of ICT is that it has created prime conditions for entrepreneurial discovery and action. This implies that there are strong motives to study various aspects of the digital economy, since ICT continues to penetrate the developed economies also after the burst of the ICT stimulated stock market bubble. In this paper we analyse one aspect of the digital economy, namely its effect of the system of functional urban regions. The motivation for this focus is that ICT offers new tools to organise information and enables major reductions in geographical transaction costs, the full implications of which is not yet well understood.

This paper analyzes the role of knowledge in regional economic growth by focusing on knowledge accessibility. The research question is the following: can the variation in knowledge accessibility between regions in a given period explain the variation in growth performance of regions in subsequent periods? A main assumption in the paper is that knowledge accessibility transforms into potential knowledge flows. Our results show that differences in growth of value‐added per employee across regions can be explained by differences in knowledge accessibility. Intra‐municipal and intra‐regional knowledge accessibilities are significant and capable of explaining a significant share of the variation in growth of value‐added per employee between Swedish municipalities. However, inter‐regional knowledge accessibility turned out to be insignificant. This is interpreted as a clear indication of spatial dependence in the sense that the knowledge resources in a given municipality tend to have a positive effect on the growth of other municipalities, conditional on that the municipalities belong to the same functional region. Thus, the results of the analysis indicate that knowledge flows transcend municipal borders, but that they tend to be bound within functional regions.

This paper analyses the aspects of spatial economics that deals with innovation, regional specialization and dynamic systems of functional regions and in particular the contributions made by the economist Börje Johansson. The innovation aspect consists of innovation networks, knowledge sources and knowledge sinks, cost and innovation of product characteristics and innovation at the industry and sector level. In the regional specialization part the infrastructure, regional economic milieus, the specialization of regions and specific the specialization in small and large regions, spatial transaction costs, and endogenous specialization are subjects that are being treated. Regional dynamics consists of location dynamics in a system of functional urban regions where different theories are being discussed as the spatial product life cycle theory and filtering-down theory. The last part does also take up lead-lag models.

We study the structure of the interregional inventor networks in Sweden by examining the residence of inventors and coinventors involved in Swedish patent applications to the European Patent Office. Several factors are found to influence the spatial affinity of regions. We find that spatial affinity extends beyond the region if it has less own R&D-related resources (business R&D, university R&D and patenting); if it is close to the other region and if it is relatively small. The resources of that other region plays a positive role if, in analogue fashion, that region has more R&D-related resources.

A shortcoming of traditional endogenous growth approaches is their assumption that the stock of knowledge is generally accessible across space. The purpose of this paper is to analyse the contribution of R&D to economic growth in Swedish municipalities, taking account of the variation in R&D accessibility among different municipalities. We argue that the interaction possibilities at different spatial scales can be properly represented by an accessibility approach which discounts interaction potentials using travel time distances. Hence, the total accessibility of a municipality is divided into (i) intra-municipal, (ii) intra-regional and (iii) extra-regional accessibility to R&D. The main result of the analysis is that knowledge accessibility in a given period has a statistically significant effect on the growth in value-added per employee in subsequent periods. Furthermore, the knowledge resources in a given municipality tend to have a positive effect on the growth of another municipality, conditional on the municipalities belonging to the same functional region. The paper also demonstrates that knowledge accessibilities do not affect growth homogenously across municipalities. By dividing the full sample into three categories, the paper shows that knowledge investments have the largest effects on regional growth in municipalities belonging to a large functional region, but not necessarily in the largest municipality in the region.