INTRA-INDUSTRY TRADE IN AGRI-FOOD PRODUCTS BETWEEN HUNGARY AND THE EU

We present an analysis of the intra-industry nature of agri-food trade between Hungary and the European Union, following the Association Agreement signed in 1991. A slight growth in intra-industry trade is indicated by the Grubel-Lloyd index. However, it is not uniform by product group or EU member state or over time, reflecting different patterns of bilateral integration and an economic restructuring process that is far from complete. Marginal intra-industry trade appears to be low, but assumes greater significance when the index is broadened to include vertical as well as horizontal trade. Thus, growth in agri-food trade between Hungary and the EU over the period 1992-98 is shown to be dominated by vertical intra-industry trade and inter-industry trade. Adjustment costs due to partial trade liberalisation are likely therefore to have been relatively high.Industrial Organization, International Relations/Trade,

Competitiveness and comparative advantage in Hungarian agriculture

We examine the competitiveness of Hungarian agriculture in relation to that of the EU, based on four indices of revealed comparative advantage, for the period 1992 to 1998. Consistency tests suggest that the indices are less satisfactory as cardinal and ordinal measures, but are useful in identifying whether or not Hungary has a comparative advantage in a particular product group. Despite significant changes in Hungarian agriculture during the 1990s, the results indicate that the pattern of comparative advantage has remained stable. Our findings suggest that Hungary has a comparative advantage for live animals and meat, but not for cereals, contradicting the findings of previous studies which have used different approaches to measuring competitiveness.

Intra-industry trade in horizontally and vertically differentiated agrifood products between Hungary and the EU

Intra-industry trade in agri-food products between Hungary and the EU is shown to be low and dominated by vertically rather than horizontally differentiated products, suggesting higher economic adjustment costs. Following recent empirical studies, we then test econometrically for the determinants of this trade using different measures of horizontal and vertical trade, and employing an array of popular explanatory variables. Results suggest that separating the measure of intra-industry trade into vertical and horizontal provides for better estimation and supports the contention that the determinants may differ by type of trade. In the regression analysis, the level of intra-industry trade is found to serve as a better dependent variable than the degree or share of intra-industry trade.

THE DYNAMICS OF AGRI-FOOD TRADE PATTERNS - THE HUNGARIAN CASE

We analyse the evolving pattern of Hungary's agri-food trade using recently developed empirical procedures based on the classic Balassa index and its symmetric transformation. The extent of trade specialisation exhibits a declining trend; Hungary lost comparative advantage for a number of product groups over the 1990s. The indices of specialisation have also tended to converge. For particular product groups, the picture is mixed: indices are reasonably stable for product groups with comparative disadvantage, but those with weak to strong comparative advantage show significant variation. The results reinforce the finding of a general decrease in specialisation, but do not support the idea of self-reinforcing mechanisms, emphasised strongly in much of the endogenous growth and trade literature.international trade, revealed comparative advantage, Hungary, International Relations/Trade,

The maintenance of sex in bacteria is ensured by its potential to reload genes

Why sex is maintained in nature is a fundamental question in biology. Natural genetic transformation (NGT) is a sexual process by which bacteria actively take up exogenous DNA and use it to replace homologous chromosomal sequences. As it has been demonstrated, the role of NGT in repairing deleterious mutations under constant selection is insufficient for its survival, and the lack of other viable explanations have left no alternative except that DNA uptake provides nucleotides for food. Here we develop a novel simulation approach for the long-term dynamics of genome organization (involving the loss and acquisition of genes) in a bacterial species consisting of a large number of spatially distinct populations subject to independently fluctuating ecological conditions. Our results show that in the presence of weak inter-population migration NGT is able to subsist as a mechanism to reload locally lost, intermittently selected genes from the collective gene pool of the species through DNA uptake from migrants. Reloading genes and combining them with those in locally adapted genomes allow individual cells to re-adapt faster to environmental changes. The machinery of transformation survives under a wide range of model parameters readily encompassing real-world biological conditions. These findings imply that the primary role of NGT is not to serve the cell with food, but to provide homologous sequences for restoring genes that have disappeared from or become degraded in the local population.Comment: 16 pages with 3 color figures. Manuscript accepted for publication in Genetics (www.genetics.org

Set Systems Containing Many Maximal Chains

The purpose of this short problem paper is to raise an extremal question on set systems which seems to be natural and appealing. Our question is: which set systems of a given size maximise the number of $(n+1)$-element chains in the power set $\mathcal{P}(\{1,2,\dots,n\})$? We will show that for each fixed $\alpha>0$ there is a family of $\alpha 2^n$ sets containing $(\alpha+o(1))n!$ such chains, and that this is asymptotically best possible. For smaller set systems we are unable to answer the question. We conjecture that a `tower of cubes' construction is extremal. We finish by mentioning briefly a connection to an extremal problem on posets and a variant of our question for the grid graph.Comment: 5 page