Browsing Discussion papers (FOR) by Author "Jörnsten, Kurt"
Now showing items 120 of 37

A maximum entropy approach to the newsvendor problem with partial information
Andersson, Jonas; Jörnsten, Kurt; Nonås, Sigrid Lise; Sandal, Leif Kristoffer; Ubøe, Jan (Discussion paper;2011:14, Working paper, 201108)In this paper, we consider the newsvendor model under partial information, i.e., where the demand distribution D is partly unknown. We focus on the classical case where the retailer only knows the expectation and variance ... 
A new Lagrangean Approach for the Travelling Salesman Problem
Jörnsten, Kurt; Kalcsics, Jörg (Discussion paper;04/15, Working paper, 20150119)In this paper, we use a reformulation of the symmetric and the asymmetric travelling salesman problem more suitable for Lagrangean relaxation and analyse the new approach on examples from TSP Lib. Furthermore the Lagrangean ... 
A New SemiLagrangean Relaxation for the KCardinality Assignment Problem
Belik, Ivan; Jörnsten, Kurt (Discussion paper;01/14, Working paper, 201401)Recently BeltránRoyo, Vial & AlonsoAyuso (2012) presented a semiLagrangean relaxation for the classical pmedian location problem and for the incapacitated facility location problem. The results, obtained using the ... 
A new SemiLagrangean Relaxation for the pmedian problem
Butsch, Alex; Jörnsten, Kurt; Kalcsics, Jörg (Discussion paper;01/15, Working paper, 20150109)Recently BeltranRoyo et.al presented a SemiLagrangean relaxation for the classical pmedian location problem. The results obtained using the SemiLagrangean relaxation approach were quite impressive. In this paper we use ... 
An analysis of a combinatorial auction
Bjørndal, Mette; Jörnsten, Kurt (Discussion paper, Working paper, 2001)Our objective is to find prices on individual items in a combinatorial auction that support the optimal allocation of bundles of items, i.e. the solution to the winner determination problem of the combinatorial auction. ... 
Analyzing learning effects in the newsvendor model by probabilistic methods
Andersson, Jonas; Jörnsten, Kurt; Lillestøl, Jostein; Ubøe, Jan (Discussion paper;13/19, Working paper, 20191011)In this paper, we use probabilistic methods to analyze learning effects in a behavioral experiment on the newsvendor model. We argue why we should believe that suggested orders follow a multinomial logit distribution, and ... 
Assessment of the Norwegian transmission pricing rules by using a modified ACOPF
Stamtsis, Georgios C.; Bjørndal, Mette; Erlich, István; Jörnsten, Kurt (Discussion paper, Working paper, 2004)This paper focuses on the combined effects of loss factors and zonal pricing in a system that takes as a starting point the procedures of transmission pricing in the Norwegian power system. It interprets the notion of loss ... 
Centrality Computation in Weighted Networks Based on EdgeSplitting Procedure
Belik, Ivan; Jörnsten, Kurt (Discussion paper;40/14, Working paper, 201412)The analysis of network’s centralities has a highlevel significance for many realworld applications. The variety of game and graph theoretical approaches has a paramount purpose to formalize a relative importance of ... 
Common mistakes in computing the nucleolus
Guajardo, Mario; Jörnsten, Kurt (Discussion paper;15/14, Working paper, 201404)Despite linear programming and duality have correctly been incorporated in algorithms to compute the nucleolus, we have found mistakes in how these have been used in a broad range of applications. Overlooking the fact ... 
Congestion management in the Nordic power market : counter purchases and zonal pricing
Bjørndal, Mette; Jörnsten, Kurt; Pignon, Virginie (Discussion paper, Working paper, 2002)In this paper, we investigate methods for managing congestion on the grid in the Nordic power market. Specifically, we have considered the differences between using counter purchases as opposed to pricing out the transmission ... 
Cooperation of customers in traveling salesman problems with profits
Osicka, Ondrej; Guajardo, Mario; Jörnsten, Kurt (Discussion paper;17/19, Working paper, 20191122)The traveling salesman problem and its variants are among the most studied problems in the literature on transportation and logistics. In one of these variants known as the profitable tour problem [2], a profitmaximizing ... 
Cost allocation in collaborative forest transportation
Frisk, Mikael; GötheLundgren, Maud; Jörnsten, Kurt; Rönnqvist, Mikael (Discussion paper, Working paper, 2006)Transportation planning is an important part of the wood flow chain in forestry. There are often several forest companies operating in the same region and coordination between two or more companies is rare. However, there ... 
A disaggregated gravity model
Gitlesen, Jens Petter; Jörnsten, Kurt (Discussion paper, Working paper, 2000)The gravity model is used to estimate trip distributions. The estimates are in form of trip frequencies. This study is devoted to an entropy problem where the solution decomposes trip frequencies to the underlying probability ... 
Efficient statistical equilibria in markets
Jörnsten, Kurt; Ubøe, Jan (Discussion paper, Working paper, 2005)In this paper we will study statistical equilibria in commodity markets where agents have a specified utility attached to every transaction in their offer sets. A probability measure on the product of all offer sets is ... 
Internal pricing in supply chains
Fjell, Kenneth; Jörnsten, Kurt (Discussion paper, Working paper, 2001)A supply chain is two or more parties linked by a flow of goods, information and funds. Since this means that supply chain management concerns environments in which there are multiple decision makers, which may be different ... 
Lower and upper bounds for linear production
Bjørndal, Endre; Jörnsten, Kurt (Discussion paper, Working paper, 200211)We study a model of a production economy in which every set of agents owns a set of resources, and where they all have access to the same technology. The agents can cooperate by pooling their resources, and the total profit ... 
Market power in a power market with transmission constraints
Bjørndal, Mette; Gribkovskaia, Victoria; Jörnsten, Kurt (Discussion papers;29/14, Working paper, 201406)In this paper we present a model for analysing the strategic behaviour of a generator and its short run implications on an electricity network with transmission constraints. The problem is formulated as a Stackelberg ... 
Mixed contracts for the newsvendor problem with real options
Jörnsten, Kurt; Nonås, Sigrid Lise; Sandal, Leif Kristoffer; Ubøe, Jan (Discussion paper, Working paper, 201104) 
Modeling freight markets for coal
Andersson, Jonas; Jörnsten, Kurt; Strandenes, Siri Pettersen; Ubøe, Jan (Discussion paper, Working paper, 200812)In this paper we study bulk shipping of coal between the central regions in the world. We compare the performance of costminimizing models with a gravity model approach. The main nding in the paper is that cost minimizing ... 
Modeling heterogeneity in tripdistributions with partial information
Jörnsten, Kurt; Kleppe, Gisle; Thorsen, Inge; Ubøe, Jan (Discussion paper, Working paper, 2007)In this paper we propose a modified gravity model that takes into account that a population generally consists of heterogeneous groups, and we suggest a new statistical test for heterogeneity. We apply our new model to two ...