The analysis of bullwhip effect in a HMMS-type supply chain

The aim of the paper is to investigate the well-known bullwhip effect of supply chains. Control theoretic analysis of bullwhip effect is extensively analyzed in the literature with the Laplace transform. This paper tries to examine the effect for an extended Holt-Modigliani-Muth-Simon model. A two-stage supply chain (supplier-manufacturer) is studied with quadratic costs functional. It is assumed that both firms minimize the relevant costs. The order of the manufacturer is delayed with a known constant. Two cases are examined: supplier and manufacturer minimize the relevant costs decentralized, and a centralized decision rule. The question is answered, how to decrease the bullwhip effect.     

Does EU Enlargement Increase Agro‐Food Export Duration?

This paper examines the impact of EU enlargement on agro‐food export performance across 12 new EU member states and five newly independent states in the EU markets covering the period 1999 to 2007. The performance is examined by duration of export and hazard model. We find larger duration for the agro‐food exports from the new EU member states. The results confirm gains from the eastward EU enlargement and governance on export increases and longer duration for exporting higher value‐added specialized consumer‐ready food and more competitive niche agro‐food products.     

Labour Market Adjustment and Intra‐Industry Trade: The Effects of Association on the Hungarian Food Industry

The structure of Hungary’s food trade expansion over the period 1995–2003 and its implications for labour market adjustment are examined. The contributions of the paper are threefold. First, we test the sensitivity of results to the choice of measurement and their implications for the results. Second, we introduce more industry‐specific control variables. Third, we distinguish the short‐ and long‐run adjustment effects. Our results provide some support for the smooth‐adjustment hypothesis of intra‐industry trade. Estimations confirm that industry‐specific variables may have a significant effect on adjustment costs.     

VALUE JUDGEMENTS IMPLIED BY THE USE OF VARIOUS MEASURES OF INCOME INEQUALITY*

If a welfare economist wants to express income inequality in a sensible way by a single parameter, he has to make rather strong assumptions regarding the social preferences of his fellow citizens. Formulas are presented with whose aid one is able to test whether or not these assumptions hold. The standard measures used nowadays contradict prevailing preferences. If no common single measure can be found which fits the social preferences of almost all individuals concerned tolerably well, additional parameters measuring poverty and riches separately are necessary.     

The relationship between the ecologisation of farms and total factor productivity: A continuous treatment analysis

The European Green Deal aims to mitigate the environmental impact of food production while improving the income of primary producers and strengthening the EU's competitiveness. We examine how the degree of ecologisation affects farms' total factor productivity (TFP). Our analysis combines a random-parameter stochastic production frontier model with a composite indicator and a dose–response function approach. Results show a monotonically decreasing relationship between ecologisation and expected TFP level. On average, a one-step increase in the degree of ecologisation results in a 12% decrease in TFP. However, the results indicate a non-linear relationship. Three regions of the dose–response function can be distinguished; associated with high, medium and low degrees of ecologisation. In a region with a low degree of ecologisation, farms can increase the degree of ecologisation without reducing TFP. Both efficiency and technological differences contribute to these differences, but the main reason is technological. With increasing ecologisation, farm technology becomes more ‘land using’. Therefore, farms can increase their TFP and degree of ecologisation simultaneously by using land-saving technologies or through sustainable intensification.     

MEASURING DISTRIBUTION MODEL RISK

We propose to interpret distribution model risk as sensitivity of expected loss to changes in the risk factor distribution, and to measure the distribution model risk of a portfolio by the maximum expected loss over a set of plausible distributions defined in terms of some divergence from an estimated distribution. The divergence may be relative entropy or another f‐divergence or Bregman distance. We use the theory of minimizing convex integral functionals under moment constraints to give formulae for the calculation of distribution model risk and to explicitly determine the worst case distribution from the set of plausible distributions. We also evaluate related risk measures describing divergence preferences.