Elimination of Source A and B Errors in p-Median Location Problems

The p-median problem is a powerful tool in analyzing facility location options when the goal of the location scheme is to minimize the average distance that demand must traverse to reach its nearest facility. It may be used to determine the number of facilities to site, as well as the actual facility locations. Demand data are frequently aggregated in p-median location problems to reduce the computational complexity of the problem. Demand data aggregation, however, results in the loss of locational information. This loss may lead to suboptimal facility location configurations (optimality errors) and inaccurate measures of the resulting travel distances (cost errors). Hillsman and Rhoda (1978) have identified three error components: Source A, B, and C errors, which may result from demand data aggregation. In this article, a method to measure weighted travel distances in p-median problems which eliminates Source A and B errors is proposed. Test problem results indicate that the proposed measurement scheme yields solutions with lower optimality and cost errors than does the traditional distance measurement scheme.     

The Shady Side of Consultation and Compensation: ‘Divide‐and‐Rule’ Tactics in Bolivia's Extraction Sector

The rights to prior consultation and compensation have been established within the framework of international indigenous peoples’ rights. However, in practice these processes have often gone hand in hand with adverse social consequences for local populations, such as the exacerbation of conflicts, the division of communities and the weakening of indigenous organizations. These phenomena have received little attention, despite their great relevance for these populations. This article sheds light on the use by the Bolivian state and extraction corporations of exclusionary participation and negotiation processes, on the one hand, and ‘carrot‐and‐stick’ techniques on the other, which have together accounted for negative social impacts on the ground. The article is based on recently conducted field research, focus group discussions and semi‐structured interviews in Guaraní communities in Bolivia. The findings extend the existing literature by providing a fine‐grained and systematic analysis of divisive undertakings and their sociocultural and sociopolitical consequences in neo‐extractivist Bolivia. The broader implications of the study add to academic debates about participation in development, about ‘divide‐and‐rule’ tactics and about the practice of indigenous peoples’ rights.     

High-skilled Return Migration and Knowledge-based Development in Poland

It is by now well known that return migration of the highly skilled can have a significant impact on knowledge-based development in the regions to which they return. Whereas previous research has mainly focused on developing and newly industrializing countries, this paper looks at high-skilled return migration in an East European transformation economy, namely Poland. In our paper, we propose an analytical framework which integrates migration theory and regional development perspectives. Based on narrative interviews with high-skilled return migrants in Warsaw and Poznań, we show that high-skilled return migrants have an impact on economic development by acting as both investors and innovators, i.e. that they transfer and successfully integrate financial means as well as different types of knowledge into these local economies. Furthermore, the Polish example illustrates that social relations and institutional context are crucial in understanding how high-skilled return migrants contribute to knowledge-based development.     

Analysis of Errors Due to Demand Data Aggregation in the Set Covering and Maximal Covering Location Problems

In this paper, we extend the concepts of demand data aggregation error to location problems involving coverage. These errors, which arise from losses in locational information, may lead to suboptimal location patterns. They are potentially more significant in covering problems than in p-median problems because the distance metric is binary in covering problems. We examine the Hillsman and Rhoda (1978) Source A, B, and C errors, identify their coverage counterparts, and relate them to the cost and optimality errors that may result. Three rules are then presented which, when applied during data aggregation, will reduce these errors. The third rule will, in fact, eliminate all loss of locational information, but may also limit the amount of aggregation possible. Results of computational tests on a large-scale problem are presented to demonstrate the performance of rule 3.     

Saami Circular Sacrificial Sites in Northern Coastal Sweden

Abstract

Saami circular sacrificial sites have been known for many years in northern Norway and northern interior Sweden. Oral or written sources regarding their origins are nevertheless lacking outside reindeer-herding areas. These circular features have now been documented in Swedish Bothnian coastal environments together with site complexes at elevations, suggesting that they were used during the Iron Age, medieval and historic periods. It is argued that these coastal features, stone circles or ring-shaped enclosures, are Saami sacrificial sites of the same character as documented in North Norway and in the mountains and the forest lands of northern Sweden.