Exports and Productivity Growth: First Evidence from a Continuous Treatment Approach

A recent survey of 54 micro-econometric studies reveals that exporting firms are more productive than non-exporters. However, previous empirical studies show that exporting does not necessarily improve productivity. One possible reason for this result is that most previous studies are restricted to analysing the relationship between a firm’s export status and the growth of its labour productivity, using the firms’ export status as a binary treatment variable and comparing the performance of exporting and non-exporting firms. In this paper, we apply the newly developed generalised propensity score (GPS) methodology that allows for continuous treatment, that is, different levels of the firms’ export activities. Using the GPS method and a large panel data set for German manufacturing firms, we estimate the relationship between a firm’s export-sales ratio and its labour productivity growth rate. We find that there is a causal effect of firms’ export activities on labour productivity growth. However, exporting improves labour productivity growth only within a sub-interval of the range of firms’ export-sales ratios. JEL no.  F14, F23, L60     

Congestion management in power systems

In liberalized power systems, generation and transmission services are unbundled, but remain tightly interlinked. Congestion management in the transmission network is of crucial importance for the efficiency of these inter-linkages. Different regulatory designs have been suggested, analyzed and followed, such as uniform zonal pricing with redispatch or nodal pricing. However, the literature has either focused on the short-term efficiency of congestion management or specific issues of timing investments. In contrast, this paper presents a generalized and flexible economic modeling framework based on a decomposed inter-temporal equilibrium model including generation, transmission, as well as their inter-linkages. The model covers short-run operation and long-run investments and hence, allows to analyze short and long-term efficiency of different congestion management designs that vary with respect to the definition of market areas, the regulation and organization of TSOs, the way of managing congestion besides grid expansion, and the type of cross-border capacity allocation. We are able to identify and isolate implicit frictions and sources of inefficiencies in the different regulatory designs, and to provide a comparative analysis including a benchmark against a first-best welfare-optimal result. To demonstrate the applicability of our framework, we calibrate and numerically solve our model for a detailed representation of the Central Western European (CWE) region, consisting of 70 nodes and 174 power lines. Analyzing six different congestion management designs until 2030, we show that compared to the first-best benchmark, i.e., nodal pricing, inefficiencies of up to 4.6% arise. Inefficiencies are mainly driven by the approach of determining cross-border capacities as well as the coordination of transmission system operators’ activities.     

Inter-industry wage differentials and strategic trade policy

Recent studies suggest that inter-industry wage differentials exist which are neither caused by different endownments of the workers with human capital, nor by different working conditions, nor by institutional rigidities. Higher employment in high-wage sectors due to exports, therefore, raises welfare. According to empirical evidence presented here more likely than not net exports from sectors paying wage premia lead to some extra gains from trade (that cannot be explained by trade policy promoting primary sectors by high amounts of subsidies per employee) for the German economy. A case is made, however, against strategic trade policy in favour of these sectors pointing to uncertainty about the amount of the differentials, their international (dis)similarity, and their sources.

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Zusammenfassung Empirische Untersuchungen deuten darauf hin, daß auch in der Bundesrepublik Deutschland Arbeitskräfte mit gleicher Humankapitalausstattung, die unter gleichen Arbeitsbedingungen in Unternehmen gleicher Größe in einer Region arbeiten, unterschiedlich entlohnt werden, wenn sie in unterschiedlichen Sektoren arbeiten. Bestehen solche Sektorlohndifferentiale, dann hat eine Ausweitung der Beschäftigung in Hochlohnsektoren positive Wohlfahrtseffekte. Es wird daher vielfach gefordert, diese primären Sektoren vor internationaler Konkurrenz zu schützen und sie durch Subventionen zu fördern. Die vorliegende Arbeit präsentiert empirische Evidenz dafür, daß die Bundesrepublik Deutschland Extra-Gewinne aus dem Außenhandel bezieht, weil zwischen der Netto-Exportquote und der Höhe des Sektorlohndifferentials ein positiver Zusammenhang besteht, ohne daß sich die Subventionspolitik an diesen Differentialen orientiert. Gegen eine gezielte Förderung der Hochlohnsektoren im Rahmen einer strategischen Handelspolitik werden dann drei Argumente vorgebracht, die mit Unsicherheiten über Höhe, internationale Ähnlichkeit und Ursachen der Differentiale zusammenhängen.

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Earlier versions of this paper were presented at the annual meeting of the international economists' group of the Verein für Socialpolitik at Hohenheim University in May 1991, at the Sixth Annual Congress of the European Economic Association in Cambridge in September 1991, and at the Universities of Hamburg and Bielefeld. I would like to thank participants at the discussions and four anonymous referees for helpful comments. The usual disclaimer applies.     

The Hot Versus Cold Effect in a Simple Bargaining Experiment

In this paper, the strategy method's impact on behavior in sequential bargaining games is investigated. Besides the decision procedure (hot versus cold), we varied the second mover punishment costs (high versus low). Significant impacts of both treatment variables were observed. For example, second movers punished significantly more often in the hot version of the low cost game. Furthermore, first mover behavior was significantly different in the hot and cold versions of both games. In the hot games, first mover behavior suggests an expectation of decreased rewards and/or punishments from second movers. We observed, however, no decrease in reward and an increase in punishment. The hot cold variable only informs first movers that the decision procedure used by second movers has changed. Therefore, first mover behavior must be shaped by their perceived assessment concerning how second movers make decisions. We argue that first mover behavior can be explained by the interaction of two well-known psychological effects: the consensus and positive self-image effects.     

Household internal and external electricity contract switching in EU countries

Using a representative sample of more than 13,000 households from eight countries in the European Union (EU), this article empirically studies the factors related to household electricity contract switching by distinguishing between internal switchers (households that switched contracts but stayed with the same supplier) from external switchers (households that switched to a new supplier). The econometric analysis includes individual preferences, household structural factors and socio-demographic characteristics, as well as electricity market characteristics. The study explicitly explores the role of risk and time preferences on switching behaviours, with risk and time preferences elicited through incentivized experiments as well as self-assessment scales. The main results suggest that internal and external switching are not related to the same factors, that risk and time preferences affect switching behaviours, and that renters are less likely to switch than homeowners; further, electricity market characteristics are found to affect household electricity contract switching.     

Problems of international development taxes

Attempts by the developing countries to replace the largely voluntary provision of development aid by a system that would free official resource flows from the possibility of political interference by the donors and from the need for yearly budgetary allocations have been going on for some time. The present author here examines the proposal of the Group of 77 for a Financing System for Science and Technology for Development.     

Liquidity supply and adverse selection in a pure limit order book market

This paper analyzes adverse selection costs and liquidity supply in a pure open limit order book market. We relax assumptions of the Glosten/Såndas modeling framework regarding marginal zero profit order book equilibrium and the parametric market order size distribution. We show that using average zero profit conditions considerably increases the empirical performance while a nonparametric specification for market order size combined with marginal zero profit conditions does not. A cross sectional analysis corroborates the finding that adverse selection costs are more severe for smaller capitalized stocks. We also find additional support for one of the central hypothesis put forth by the theory of limit order book markets, which states that liquidity supply and adverse selection costs are inversely related. Furthermore, adverse selection cost estimates based on our structural model and those obtained using popular model-free methods are strongly correlated. This indicates the robustness of the theory-based approach.     

Integrating machine learning and workflow management to support acquisition and adaptation of workflow models

Current workflow management systems (WFMS) offer little aid for the acquisition of workflow models and their adaptation to changing requirements. To support these activities we propose to apply techniques from machine learning, which enable an inductive approach to workflow acquisition and adaptation. We present a machine learning component that combines two different machine learning algorithms: the first induces the structure of sequential workflows and the second is responsible for the induction of transition conditions. The second task can be solved by applying standard decision rule induction algorithms. In this contribution we focus mainly on the algorithms for the first task. For this purpose we describe two algorithms based on the induction of hidden Markov models. The first algorithm is a bottom‐up, specific‐to‐general algorithm and the other applies a top‐down, general‐to‐specific strategy. Both algorithms have been implemented in a research prototype. In six scenarios we evaluate and compare the two algorithms experimentally. The induced workflow models can be imported by the business process management system ADONIS. Copyright © 2000 John Wiley & Sons, Ltd.     

Factors Affecting Technical Efficiency among Coffee Farmers in Côte d’Ivoire: Evidence from the Centre West Region

This paper presents measures of technical efficiency for a sample of 81 peasant farmers in the low‐income region of Côte d’Ivoire. DEA techniques were used to compute farm‐level technical efficiency (TE) measures. The analysis reveals average levels of technical efficiency equal to 36 per cent and 47 per cent respectively for the CCR ( Charnes et al., 1978 ) and BCC ( Banker et al., 1984 ) models. These results suggest that substantial gains in output and/or decreases in cost can be attained given existing technology. In a second step analysis, two‐limit Tobit regression techniques were used to examine the relationship between TE and various farm/farmer characteristics. From a policy point of view, an important conclusion stemming from the analysis of our sample is that family size, membership to farmer's club or association and the origin of the farmer are the variables found to be most promising for action. The analysis suggests that policymakers should foster the development of the formal farmers’ club or association by building the capacity of the farmers. Our analysis also supports the argument for public sector involvement in the provision of information on labour force management to peasant farmers as a means to improve efficiency levels, and thus household incomes.