Fairs for e-commerce: the benefits of aggregating buyers and sellers

In recent years, many new and interesting models of successful online business have been developed. Many of these are based on the competition between users, such as online auctions, where the product price is not fixed and tends to rise. Other models, including group-buying, are based on cooperation between users, characterized by a dynamic price of the product that tends to go down. There is not yet a business model in which both sellers and buyers are grouped in order to negotiate on a specific product or service. The present study investigates a new extension of the group-buying model, called fair, which allows aggregation of demand and supply for price optimization, in a cooperative manner. Additionally, our system also aggregates products and destinations for shipping optimization. We introduced the following new relevant input parameters in order to implement a double-side aggregation: (a) price-quantity curves provided by the seller; (b) waiting time, that is, the longer buyers wait, the greater discount they get; (c) payment time, which determines if the buyer pays before, during or after receiving the product; (d) the distance between the place where products are available and the place of shipment, provided in advance by the buyer or dynamically suggested by the system. To analyze the proposed model we implemented a system prototype and a simulator that allow to study effects of changing some input parameters. We analyzed the dynamic price model in fairs having one single seller and a combination of selected sellers. The results are very encouraging and motivate further investigation on this topic

How political parties, rather than member-states, are building the European Union

Political party formation and coalition building in the European Parliament is being a driving force for making governance of the highly pluralistic European Union relatively effective and consensual. In spite of successive enlargements and the very high number of electoral parties obtaining representation in the European Union institutions, the number of effective European Political Groups in the European Parliament has decreased from the first direct election in 1979 to the fifth in 1999. The formal analysis of national party¹s voting power in different European party configurations can explain the incentives for national parties to join large European Political Groups instead of forming smaller nationalistic groupings. Empirical evidence shows increasing cohesion of European Political Groups and an increasing role of the European Parliament in EU inter- institutional decision making. As a consequence of this evolution, intergovernmentalism is being replaced with federalizing relations. The analysis can support positive expectations regarding the governability of the European Union after further enlargements provided that new member states have party systems fitting the European Political Groups.Political parties, coalitions, power indices, political institutions, European Union

Aggregation and Representation in the European Parliament Party Groups

While members of the European Parliament are elected in national constituencies, their votes are determined by the aggregation of MEPs in multinational party groups. The uncoordinated aggregation of national party programmes in multinational EP party groups challenges theories of representation based on national parties and parliaments. This article provides a theoretical means of understanding representation by linking the aggregation of dozens of national party programmes in different EP party groups to the aggregation of groups to produce the parliamentary majority needed to enact policies. Drawing on an original data source of national party programmes, the EU Profiler, the article shows that the EP majorities created by aggregating MEP votes in party groups are best explained by cartel theories. These give priority to strengthening the EP’s collective capacity to enact policies rather than voting in accord with the programmes they were nationally elected to represent

Negotiating a stable government - an application of bargaining theory to a coalition formation model

In this paper, we apply bargaining theory to a certain model of coalition formation. The notions of a feasible government and a stable government are central in the model considered. By a government, we mean a pair consisting of a majority coalition and a policy supported by this coalition. The aim of this paper is to establish which stable government should be created if more than one stable government exists or, in case there is no stable one, which feasible government should be formed if more than one feasible government exists. Several bargaining procedures leading to the choice of one stable (or feasible) government are proposed. We define bargaining games in which only parties belonging to at least one stable (or feasible) government bargain over the creation of a government. We consider different bargaining costs. We investigate subgame perfect equilibria of the bargaining games defined. It turns out that the prospects of a party depend on the procedure applied, and on the bargaining costs assumed. We also apply the coalition formation model to the Polish Parliament after the 2001 elections and apply the different bargaining games for the creation of a government to this example.stable government; bargaining game; subgame perfect equilibrium

The Dynamics of Political Parties’ Coalition in Indonesia:\ud The evaluation of political party elites’ opinion

During the Indonesian president election process, the coalition of parties could be shown as the dominant process beside the president campaign. The coalition could be regarded as the emergence of the parties’ preferential coherence based upon the interest and attributes of each party. The similarity and difference of parties’ preference and attributes could be depicted through of party elites’ opinions and attitude toward flowered political issues. In this paper, we use the Heider’s balance theory to construct relation network among parties by using the longitudinal news data of the party elite’s opinion that published by the media, and then analyze the dynamic of coalition formation in the Indonesian political system during the election process. We have shown that the balance of the party’s relational network move toward the larger balance index relative to the initial condition. This phenomenon has verified the structural balance hypothesis especially for the conflict situation such as the election process. Interestingly, the balance of the system is fluctuated dynamically through time following certain trajectory. This dynamics is divided into 3 phases, that is, disorder state, conflict state, and order state, as well as signed the difference of party behavior before and after the legislative election. Moreover, we also analyzed the stability two parties’ relation in particular period in order to understand specifically the dynamic of the system in triadic level

Measuring voting power in convex policy spaces

Classical power index analysis considers the individual's ability to influence the aggregated group decision by changing its own vote, where all decisions and votes are assumed to be binary. In many practical applications we have more options than either "yes" or "no". Here we generalize three important power indices to continuous convex policy spaces. This allows the analysis of a collection of economic problems like e.g. tax rates or spending that otherwise would not be covered in binary models.Comment: 31 pages, 9 table