AN ECONOMIC RESPONSE MODEL OF HERBICIDE APPLICATION FOR WEED CONTROL

A biologically realistic model of crop yield response to herbicide application is presented. It includes functions for weed mortality from herbicide application and yield loss due to surviving weeds. The optimal herbicide rate and two types of decision thresholds are derived theoretically and illustrated with empirical examples. Responses of the various decision criteria to changes in parameters are also examined theoretically and empirically. A multidimensional threshold for weeds based on weed density and weed-free yield is presented. The issue of farmers using other than officially recommended herbicide rates is discussed.     

The Surge in Short-Duration Contracts in Spain

Until the outbreak of the recent economic and financial crisis, Spain was leading the ranking of countries with the largest share of temporary employees. During the crisis this share has fallen to its lowest level in decades, but this does not mean that working conditions in Spain have improved. The flow of new temporary contracts is larger than ever before. A particularly striking feature is the steep growth in the volume of fixed-duration contracts lasting less than a week or a month. We document these trends and analyse how this phenomenon has affected the transition from temporary to permanent employment.     

Endogenous timing in trade policy games: Should governments use countervailing duties?

Endogenous Timing in Trade Policy Games: Should Governments Use Countervailing Duties? - Trade policy under oligopoly is analysed in two multistage games with endogenous timing of trade policy. At the beginning of the games, the domestic and foreign governments choose whether to set trade policy at stage one or two. It is shown that in the subgame perfect equilibrium of both games, the domestic government will set its tariff (and production subsidy) at stage one and the foreign government its export subsidy at stage two. The domestic country commits not to use a countervailing duty in both games, and both countries are better off than when they set trade policy simultaneously.     

Testing for non-linear dependence in inter-war exchange rates

Testing for Non-Linear Dependence in Inter-War Exchange Rates. — This paper tests weekly inter-war floating exchange rate data for the pound-dollar, pound-franc and pound-reichsmark for non-linearity. Initial tests reveal strong evidence of generic non-linearity in these series and indicate neglected non-linear structure in the residuals of linear representations. Attempts to model this structure using GARCH residual processes have only been partially successful. Thus, two parametric models of such non-linearity were estimated. Comparing the forecasts from these models shows the mean square forecast errors of linear-GARCH and bilinear models to be lower than those from linear forecasts for all series, and that SETAR model forecasts outperform all other models for the pound-dollar.     

Employment response to supply and demand shocks under envy in wage formation

Summary We analyse the impact of wage envy on employment and on its sectorial allocation. A multi-sector general equilibrium model in which externalities among sectors arise through wage envy and decentralized bargaining is presented. In the no externality case, sectorial employment is a function of sectorial productivity and of the disutility of work. In the externality case, sectorial employment is additionally affected by union power in all sectors (with a negative sign even though bargaining is efficient), by the productivity in the other sectors (with an undetermined sign) and by the relative average propensity to consume goods of this sector (with a positive sign).Rijksuniversiteit Limburg, FNRS and Université Catholique de Louvain. I would like to thank Franz Palm for valuable comments on an earlier draft. This paper benefitted also from discussions with Torben Andersen, Jacques Drèze and Henri Sneessens (without implying them in any mistake). The detailed comments of the anonymous referee contributed to a large extent to clarify the exposition of the model.     

Output Expectations and Forecasting of UK Manufacturing

This paper analyses both quarterly data from the Confederation of British Industry (CBI) Survey on respondents’ expectations of recent and forthcoming manufacturing output and monthly Office of National Statistics (ONS) figures on actual manufacturing output within the UK. Quarterly output expectations of the CBI manufacturers are explained from the monthly ONS observations using a bounded rationality approach. The logistic formulation models the diffusion process across respondents. There is a backward-looking CBI Survey perspective, explained by past ONS observations, and a forward-looking perspective, explained from future ONS statistics. Also, the forecasting of monthly manufacturing output from earlier values, along with the quarterly CBI Survey information, is examined and tested against the alternative Pesaran/Thomas method. The study provides econometric evidence for the validity of the logistic model and shows that bounded rationality can explain the formation of predictions among business managers in the UK manufacturing sector. The emerging consensus from the literature, supported by this paper, is that the logistic format is a superior approximation to the true data generating process compared with the earlier standard Anderson/Pesaran/Thomas approach. An adjustment to the Survey is used, which achieves perfect symmetry with up and down versions of the data. The benefits of this adjustment are tested in the forecasting section.

Corporate Lobbying and Firm Performance

Corporate lobbying activities are designed to influence legislators, regulators and courts, presumably to encourage favorable policies and/or outcomes. In dollar terms, corporate lobbying expenditures are typically one or even two orders of magnitude larger than spending by Political Action Committees (PAC), and, unlike PAC donations, lobbying amounts are direct corporate expenditures. We use data made available by the Lobbying Disclosure Act of 1995 to examine this more pervasive form of corporate political activity. We find that, on average, lobbying is positively related to accounting and market measures of financial performance. These results are robust across a number of empirical specifications. We also report market performance evidence using a portfolio approach. We find that portfolios of firms with the highest lobbying intensities significantly outperform their benchmarks in the three years following portfolio formation.