Nonparametric Evaluation of Economies of Scope in the Context of Technical Efficiency: The Case of Rice and Vegetable Farms in Korea

This paper provides a nonparametric evaluation of economies of scope in the context of technical efficiency allowing for non‐convexity, with an application to Korean rice and vegetable farms. Relying on non‐parametric‐free disposal hull and data envelopment analysis approaches and input–output data for rice and vegetable farms from the Korea Farm Household Economy Survey data collected in 2007, this article examines technical inefficiency and its decomposition under non‐convexity and convexity. Empirical measures of technical inefficiency and its decomposition results are provided, with a focus on a component of technical inefficiency associated with economies of scope (i.e. diversification benefits) under non‐convexity in production technology. The decomposition measures of technical inefficiency include pure technical inefficiency, size inefficiency and diversification inefficiency. The results provide empirical evidence supporting size‐dependent diversification strategies, where benefits of diversification are larger for small farms on average compared to those of large farms.     

A Heteroskedastic Multivariate Tobit Analysis of Price Dynamics in the Presence of Price Floors

This article presents an econometric analysis of the effects of price floors on price dynamics and price volatility in a multimarket context. We investigate the implications of a government price-support program providing a censoring mechanism to the price determination process. The analysis uses a dynamic multivariate Tobit model under time-varying volatility. The model is applied to the U.S. dairy markets with a special focus on the effects of government price-support programs in a period of market liberalization. The econometric analysis provides useful information on the multimarket effects of price supports on price dynamics and price volatility.     

Specialization,diversification, and productivity: a panel data analysis of rice farms in Korea

This article examines the microeconomics of productivity associated with specialization/diversification in production activities, with an application to Korean rice farms. Korean rice farms tend to be very small and highly specialized. Our analysis examines the productivity effects associated with both farm size and farm specialization/diversification in Korean agriculture. Relying on farm‐level panel data, the analysis studies farm productivity in a multi‐input multi‐output context, accounting not only for changes in inputs and technical change in rice production, but also for the role of diversification in the production of other crops in current and previous periods. We find positive but small productivity gains from farm diversification. These gains come mostly from complementarity effects across farm outputs, with minimal effect of scale economies. The positive complementarity effects work against nonconvexity effects, which provide strong productivity incentives for rice farms to specialize.     

Technological change and risk management: an application to the economics of corn production

The paper investigates the linkages between technological change and production risk, with an application to corn. The effects of technology on risk exposure are analyzed. We define technological progress to be risk‐increasing (risk‐decreasing) if it increases (decreases) the relative risk premium. The analysis is applied to panel data from Wisconsin research stations. Conditional moments (including mean, variance and skewness) of corn yield, grain moisture and corn profit are estimated for different sites. We investigate how the trade‐off between expected return and the risk premium varies over time and over space. The empirical results indicate that technological progress contributes to reducing the exposure to risk as well as downside risk in corn production, although this effect varies across sites. They also stress the role of the relative maturity of corn hybrids as a means of managing risk.     

Cointegration relationships and hedonic pricing of differentiated commodities: an application to price dynamics in the US dairy sector

This study investigates the implications of hedonic pricing for price dynamics of differentiated commodities. A conceptual model of hedonic pricing is developed under a Leontief technology, showing how commodity prices reflect the underlying value of their components. Implications for the existence of cointegration relationships among commodity prices are derived. An application to the pricing and dynamics of selected US dairy commodities is presented. It provides evidence on the role of component valuation in the dynamics of dairy commodity prices in the short run as well as in the long run. Distinguishing between market regime and government regime (when the government price support is active), the analysis finds significant differences in dairy price dynamics between the two regimes.     

Efficiency and technological change at US research universities

This article investigates the determinants of efficiency and technological progress at US research universities. It relies on a unique panel data set of multiple outputs and inputs from 92 universities covering the period 1981–1998. Over that time span, US universities experienced large increases in industry funding and in academic patenting activity. In this context, the directional distance function and a nonparametric representation of the underlying production technology are combined to obtain estimates of productivity growth and technical efficiency. An econometric analysis is then presented to examine the determinants of technical efficiency and the rate of technological progress. The results show how changes in funding sources for US research universities affects research performance.     

A Dynamic Analysis of University Agricultural Biotechnology Patent Production

This article examines the factors that account for agricultural biotechnology patenting success among universities using a dynamic count data model. It builds a theoretical and econometric model to capture the inherently dynamic and nonlinear process of technological innovation, wherein a feedback mechanism from previous success partially determines current patent counts. The econometric estimates reveal the importance to agricultural biotechnology patent production of land grant infrastructure, quality faculty, patent-oriented technology transfer offices, as well as dynamic feedback effects.     

Trends in University Ag-Biotech Patent Production

This work exploits information on U.S. patents to identify trends in university ag-biotech patenting and citation performance. It sets forth some key issues concerning patterns of university ag-biotech patenting and then provides an empirical analysis of the evolving trends. Land grant universities account for most U.S. ag-biotech patents. The data show a path-dependent innovation pattern, in which there also seems to be a culture of patenting that develops at certain universities. Evidence shows that ag-biotech patents are more cited than the average university patent. Inequalities across land grant universities are also evident in the production of ag-biotech patents, although perhaps not to a much greater degree than underlying inequalities in funding and research qualities. The paper closes by considering how the evidence offered might be used to advance the public discussion regarding trends in agricultural biotechnology research in the United States.     

Strategic International Diversification and Monthly Seasonality

To the author's knowledge no other studies have dealt with the effect of international diversification on stock market monthly seasonality. The aim of this study is to investigate this effect in various ways: stock market monthly seasonality is analyzed by incorporating exchange rates and trading costs in international portfolio returns. The variance of the world portfolio is decomposed into six components. Stochastic dominance approach is used to show the robustness of the results. Five trading strategies are compared to help international investors be more informed. All the results show that monthly seasonality is clearly present in an economic sense and robust. Particularly, when exchange rates are incorporated into portfolio returns. January has the highest return and the lowest risk in the world portfolio.     

Measuring soil quality dynamics A role for economists, and implications for economic analysis

Measuring soil quality is extremely difficult, yet it has clear economic importance. In particular, there is a great deal of empirical interest in the dynamics of soil quality evolution when land managers respond to policies and other incentives. Yet current methodologies for measuring changes in agricultural land quality are largely static and rely heavily either on incomplete measures such as proxy variables, or ad hoc indexes of selected soil characteristics. Moreover, much empirical work relies on static econometric techniques or simulation models. In this paper, we develop a means to infer soil quality changes from input and output data using a dynamic production function model. Using data from field experiments, we estimate the model in a way that allows the recovery of a dynamic measure of soil quality whose evolution depends on variations in management practices. Our methodology and findings will help provide firmer empirical foundations for analyses of the economic implications of land degradation and the soil quality implications of agricultural policies.