Structural changes in Swedish wastepaper demand: a variable cost function approach

The primary purpose of this paper is to analyse the short-run price responsiveness of wastepaper demand in Sweden for four different paper and board products, as well as any structural changes in demand behaviour for these products over time. The analysis is done within a variable Translog cost function model, and we employ data for individual paper and board mills over the time period 1974-1994. The results suggest that the short-run own-price sensitivity of waste paper demand is relatively high compared to those of other input factors, and it has also tended to increase over time for some of the paper products. In addition, wastepaper demand has also become more sensitive to changes in energy prices, and its use increases with increases in the price of energy. However, the relationship between wastepaper and woodpulp is more complex, and in many instances wastepaper and woodpulp are short-run complements. Overall this implies that price based recycling policies will be relatively successful in promoting wastepaper use, but they will not necessarily lead to the conservation of virgin forest resources.     

Technology and efficiency in a panel of Italian dairy farms: an SGM restricted cost function approach

This article employs a short‐term specification of the symmetric generalised McFadden (SGM) cost function capable of accommodating quasi‐fixed factors and variable returns. Temporary equilibrium and scale economies are investigated while maintaining the consistency of the estimated model with microeconomic theory and approximation properties. It also makes use of a two‐step procedure to estimate first the technology parameters and then time‐varying efficiency at farm level. No distributional assumptions are required on efficiency as we consider a fixed effect model. A balanced panel of Italian dairy farms during the years from 1980 to 1992 serves as the case study. The results suggest a rigid productive structure during the pre‐ and post‐quota period. Moreover, Italian milk producers are found to exhibit considerable excess capacity and rather low input technical efficiency.     

Estimating the economic value of big game habitat production from prescribed fire using a time series approach

This paper demonstrates a time-series production technique to quantify the deer harvest and deer hunting benefits of controlled burns or prescribed fire. The time series regression model showed a statistically significant and positive effect of prescribed fire on deer harvest. The net economic value of the resulting additional deer hunting benefit was estimated using the Contingent Valuation Method at $ 98 per additional deer harvested. The initial deer hunting benefits of an additional 1,000 acres of prescribed burning are between $ 2,674 and $ 3,128 or $ 2-3 per acre. The costs of prescribed burning greatly exceed these benefits, suggesting that deer hunting benefits represent only a small part of the multiple use benefits of prescribed fire.     

Estimating the economic cost of weeds in Australian annual winter crops

An analysis of the annual costs of weeds in seven winter crops across Australia demonstrated that the most important 15 weed species cause substantial annual costs in both financial and economic terms. Using survey data captured over the 1998–1999 growing season, the financial cost of these weeds in seven crops was estimated to be AU$1,182 million. The main components of this cost were herbicides (AU$571 million), the competitive effects of residual weeds (AU$380 million), and tillage (AU$206 million) while weed contamination of grain was a minor cost (AU$25 million). Across all regions, the most economically important weeds were annual ryegrass, wild oats, and wild radish, although there were regional differences in importance. An economic surplus analysis determined the annual economic cost of weeds in annual winter crops to be AU$1,279 million. This surplus loss represented 17% of the gross value of Australian grain and oilseed production in 1998–1999. Australian grain producers incurred a major loss, with a reduction in producer surplus of AU$1,047 million. Australian grain consumers had a large consumer surplus loss (AU$229 million), while international consumers suffered a small loss and international grain producers gained a small producer surplus from the higher grain prices.     

灌溉管道造价函数研究

确定某个地区的灌溉管道的造价函数,需要收集当地单位长度灌溉管道的工程造价资料,但目前造价资料收集较为困难,且有些管道灌溉工程建设年代较早,其造价已不能反映目前的价格水平。针对以上问题,引入市场材料造价信息、工程预算定额等内容计算各种管径管道的工程单价,再经过统计分析得出灌溉管道造价函数。     

Re‐examination of production,cost, and restricted profit functions using quantile regression approach

This article estimates quantile regressions of production, cost, and restricted profit functions using a Cobb‐Douglas functional form with non‐Hicks neutral technology change. In contrast to previous studies, quantile regression estimates reveal the relationship between the independent (production, cost, and restricted profit) and dependent (input quantities and prices) variables at each quantile of the distribution. An empirical application using data from 48 states in United States from 1960 to 2004 indicates the returns to scale and aggregate technology not only differ across production, cost, and restricted profit functions but across states in different quantiles of the distribution. This suggests the traditional measures of returns to scale and aggregate technology are under‐ and overestimated in states at upper and lower quantiles, respectively.     

Estimating overall returns to international agricultural research in Africa through benefit-cost analysis: a "best-evidence" approach

This study offers a "best evidence" approach to summarizing recent benefit-cost analyses of international agricultural research in Africa. First, from an extensive literature review and the resulting global inventory of impact studies, 23 studies are identified that calculate aggregate rates of return for Consultative Group on International Agricultural Research (CGIAR) and partner investments in Sub-Saharan Africa (SSA). These studies are then appraised against a review framework consisting of principles, criteria, and indicators for study rigor. Subsequently, the economic benefits reported by studies grouped on the basis of its analytical rigor are aggregated and set against total investment by the CGIAR and national agricultural research systems to determine if the total investment to date can be justified by documented benefits under a range of assumptions. As a result, the study finds that aggregate investment is justified under a fairly wide range of suppositions. Under all scenarios, the vast majority of documented benefits stem from a relatively limited array of activities with a majority of benefits stemming from biological control (80%). Close to 20% of total benefits result from crop genetic improvement, and less than 1% result from all other activities. The implications of these results for research investment strategies in SSA and impact assessment are discussed.     

胶州湾填海造地海域折耗成本分析——基于使用者成本法

填海造地将海洋变成陆地,彻底改变了海域属性,造成海域资源的一次性折耗。论文基于使用者成本法,分别依据被填海域产生的土地价值和丧失的生态系统服务功能机会收益,对比计算胶州湾填海造地海域资源折耗成本。结果显示：2007～2011年,在4.3％折现率下,以填海生成的土地价值作为资源收益,胶州湾填海造地的海域资源折耗成本分别为4858～19464万元,同期征收的海域使用金占海域资源折耗成本的44％～58％;以被填海域生态系统服务价值作为海域资源收益,其折耗成本为4139～13506万元,同期征收的海域使用金占海域资源折耗成本的52％。93％。结果表明,填海造地的海域使用金未能完全反映被填海域的资源折耗成本。该结论可为围填海造地海域使用金征收标准的动态管理提供依据。     

Raising offtake from cattle grazed on natural rangelands in sub-Saharan Africa: a transaction cost economics approach

Farmers in sub‐Saharan Africa are constrained by large transaction costs associated with marketing of their livestock. However, transaction costs are often not taken into account in the analysis of factors hampering the development of livestock marketing in this region. This article empirically measures the influence of transaction costs on the offtake from cattle grazed on natural rangelands in Uganda. The study is based on the monitoring of 696 cattle transactions in three districts of Uganda from August 2004 to August 2005. The estimated models suggest that proportional transaction costs represented by the state of roads, distance to markets, and time taken to reach the market are important variables constraining market participation. In order to raise offtake from the national herd, it is essential to explicitly address these costs. One potential solution is collective action in marketing of livestock in which proportional and fixed transaction costs are reduced and shared among the group members.     

Food consumption dynamics: a nonparametric approach using maximum entropy estimation

We model dynamic consumer choice in a stochastic optimal control framework and show conditions under which observable market share data possess the Markov property. Using 30 years of annual aggregate milk consumption data differentiated by fat content, maximum entropy is used to estimate nonstationary transition probabilities showing how consumer tastes and preferences have changed over time. The maximum entropy approach allows for the estimation of a 4 × 4 transition probability matrix for each year of the sample. Results suggest that skim milk was an absorbing state over most of the sample but that the trend toward skim milk has decelerated and possibly reversed itself since 1998. Our approach provides a useful complement to existing parametric approaches to demand analysis when data are limited or the problem is ill‐posed.     

Regional economic impacts of a plant disease incursion using a general equilibrium approach*

The present study uses a dynamic multiregional computable general equilibrium (CGE) model to estimate the micro‐ and macroeconomic effects of a hypothetical disease or pest outbreak. Our example is a Karnal bunt incursion in wheat in Western Australia. The extent of the incursion, the impact of the disease or pest on plant yields, the response of buyers, the costs of eradication and the time path of the scenario contribute to outcomes at the industry, regional, state and national levels. We decompose the contribution of these individual direct effects to the overall impact of the incursion. This might provide some guidance regarding areas for priority in attempting to eradicate or minimise the impacts of a disease or pest. The study also introduces a theory of dynamic regional labour adjustment in which economic events may lead to both real wage differentials and worker migration between regions.     

Efficiency estimation in a profit maximising model using flexible production function

This paper uses a flexible (translog) production function to estimate efficiency of 227 farms from West Bengal, India. We consider estimation of technical and allocative inefficiencies using a profit maximising framework which accommodates both endogenous and exogenous inputs. The maximum likelihood method of estimation developed in this paper is based on the production function and the first-order conditions of profit maximisation. Farm-specific technical and allocative inefficiencies are also estimated. Empirical results show that the mean level of technical efficiency is 75.46% while the best farm is 85.87% efficient (technically). So far as allocative efficiency is concerned the majority of the farms are found to be under-users of the endogenous inputs, viz., fertiliser, manure, human and bullock labour.