production contracts and productivity in the u s hog sector this article measures the impact of contracting on partial and total factor productivity and the production technology of u s hog operations a sample selection model accounts for the fact that unobservable variables may be correlated with both the operators decision to contract and farm productivity results indicate that the use of production contracts is associated with a substantial increase in factor productivity and represents a technological improvement over independent production results also identify determinants of farmers decisions to contract and other factors influencing farm the rapid increase in the use of production contracts is a notable feature of the structural change taking place in the us hog industry between 1992 and 1998 the portion of feeder pig to finish hog operations using production contracts increased from 11 to 34 while the share of output produced under contract increased from 22 to 63 mcbride mcbride and key production contracts offer several potential advantages over independent production that could explain their growing prevalence contracts may serve to lower transaction costs associated with search negotiation and transfer reduce asymmetric information between growers and processors about product quality improve coordination of product delivery and lower income risk for growers in addition contracting may raise farm productivity by improving the quality of managerial inputs by speeding the transfer of technical information to growers or by facilitating growers access to credit thereby permitting the adoption of newer more efficient technologies in this article we focus on identifying and measuring the farm level productivity gains if any that can be attributed to contracting the recent growth in contracting does not necessarily imply that contracts are associated with higher farm productivity the increase in the use of contracts may have been propelled

the effects of changes of the job offer arrival rate on the duration of unemployment generally it is acknowledged that changing the job offer arrival rate has two opposite effects on unemployment duration for a basic job search model sufficient conditions on the wage offer distribution have been derived ensuring that one of the effects dominates however these are not satisfied for the popular families of wage offer distributions here i show that the conditions can be weakened at virtually no cost the set of distributions satisfying the new conditions is considerably larger than the set previously established in particular it includes all wage offer distribution families that are popular in structural empirical research

what happens when food marketers require restrictive farming practices the dimensions that define a food product have expanded rapidly to include characteristics of the production process marketing arrangements and implications that production and consumption of the product have for the environment some market intermediaries have responded by requiring that their suppliers abide by restrictive production practices we examine the economic effects of such restrictions and apply this analysis to limitations on the use of antibiotics in u s pork production results from conceptual and simulation analyses show that in the absence of demand growth less pork is sold due to higher costs in the restricted segment and both pork consumers on average and producers are harmed demand growth of between 6 11 from adding new consumers who will consume the restricted antibiotic free product but not the conventional product is needed to return consumer surplus to the level in the base case and between 2 4 demand growth was required to return producer surplus to base when restricted and conventional products are modeled using a vertical differentiation framework results depend importantly on the ease with which consumers can switch to a seller who offers their desired product type significant distributional impacts among consumers are present when switching costs are prohibitive

worker heterogeneity job screening and firm size a model of job screening is developed in which firms make wage offers to workers based on an imperfect evaluation of their abilities if large firms have higher costs of acquiring information about workers they screen workers with less accuracy and choose a wage compensation scheme different from the one small firms choose this generates the often observed positive correlation between firm size and wages the model also predicts that wage structure and perhaps wage dispersion will differ by firm size and that individuals who acquire more schooling will also choose to work in a larger firm these hypotheses are tested and supported using data from the national longitudinal survey

job search and commuting time we structurally analyze a job search model for unemployed individuals that allows jobs to have different wage commuting time combinations the structural parameter of interest is the degree of willingness to pay for commuting time we use a unique dataset containing responses by unemployed individuals on the optimal search strategy to estimate this parameter without the need to rely on functional form assumptions we address specification errors in the model and measurement errors in the data the results identify types of individuals who have a high disutility of commuting time

the econometrics of damage control why specification matters the contribution of damage control agents to production differs fundamentally from that of standard inputs lands labor capital this paper develops an econometric model based on the key characteristics of damage control agents and examines its properties it demonstrates that standard production function specifications overestimate damage control agent productivity and have erroneous implications for the evolution of damage control agent productivity and use in response to changing environments e g the spread of pest resistance it also proposes several alternative specifications and discusses methods for estimating them

estimating reservation wages of employed workers using a stochastic frontier according to search theory workers form reservation wages such that employment offers paying wages less than the reservation wage are rejected the first job offer paying a wage higher than the reservation wage is accepted and search is terminated though the reservation wage is clearly a matter of individual taste and unobservable a number of empirical articles have nevertheless appeared on the subject the present paper adds to this literature its novel aspects are that it uses data on employed workers rather than unemployed workers as is usually the case and that it applies a comparatively new econometric technique stochastic frontier estimation to the problem of estimating reservation wages our interests in this paper are twofold first the paper provides estimates of worker reservation wages utilizing the stochastic frontier regression technique second we use these estimates to test various hypotheses regarding the response of reservation wages to factors that search theory suggests are important in the determination of reservation wages the remainder of the paper is organized as follows section ii discusses the previous empirical literature on the reservation wage section iii sketches the theory and estimation techniques we use section iv lays out a framework for assessing the validity of the approach used here finally section v presents the empirical results

reservation wages expected wages and unemployment we model unemployment duration reservation and expected wages simultaneously for individuals not in work where wage expectations are identified via an exogenous policy shock the policy shock increased expected wages which were found to be positively associated with reservation wages

competition between and within teams abstract we consider the effect of team size the observability of effort and the competitiveness of the team s environment in determining team members allocations of effort between team oriented and selfish efforts

an econometric analysis of reservation wages this paper describes an analysis of survey data on unemployed people who reported their asking wage and the wage they expected to earn we show that if agents behavior is described by the standard optimal job search model one can use these data to deduce structural parameters rather than estimate them and we report our deductions from two surveys 1 of british unemployed people

animal health inputs endogenous risk general infrastructure technology adoption and industrialized animal agriculture abstract this paper develops a microeconomic model of concentrated animal feeding operations that admits roles for all of animal health inputs genetic profile choices and the pertaining economic infrastructure the basic model emphasizes how time on feed feed density and biosecurity choices interact as well as how these choices respond to i input prices and ii attributes regarding animal productivity parameters that might be influenced by policy choices such as animal welfare strictures and restraints on use of medication we show that ostensibly substituting inputs in protecting against animal health risks may in fact be complements and that the model s production choices come as a complementary package we then extend the model to endogenize the choice of animal genetics a finding is that innovations in general infrastructure encourage herd owners to choose more feed efficient but less hardy animals higher feed conversion efficiency then induces the use of denser feed rations accelerated finishing and greater levels of biosecurity actions at farm perimeters our theory provides a coherent framework for explaining associations among inputs and outcomes that are linked with confined animal agriculture it also explains how animal protein supply chain technology adoption and performance can differ according to a region s state of infrastructure why responses to a change in infrastructure may be large and why public sector efforts to reduce production risk may beget private sector effort to do so

a structural dynamic analysis of job turnover and the costs associated with moving to another job this paper provides an empirical analysis of the labor market behavior of employed individuals using a structural on the job search model the costs associated with moving to another job are allowed to be nonzero and may depend on the wage level it is shown that under certain conditions the optimal strategy has the reservation wage property the model is estimated using data on job durations and subjective responses concerning the search strategy the results reveal some strong sources of inflexibility of the labor market copyright 1992 by royal economic society

sub therapeutic antibiotics and the efficiency of u s hog farms antimicrobial drugs are frequently fed to hogs at sub therapeutic levels to promote feed efficiency and growth however in response to concerns that sub therapeutic antibiotics stas are promoting the development of antimicrobial drug resistant bacteria the u s food and drug administration recently adopted a strategy to phase out antibiotics for such production uses this study uses a stochastic frontier model to estimate the costs to u s hog producers of a ban on stas for growth promotion to address potential sample selection issues we employ a recently developed empirical approach that corrects for biases from both observed and unobserved variables

simple econometrics of pesticide productivity this paper develops a multioutput generalization of the lichtenberg zilberman damage control technology the dual representation of the technology is shown to be conditionally additive in the price of abatement activities and other prices an econometric procedure for estimating the dual technology is developed and applied to an aggregate u s agricultural data set the conditionally additive nature of the model allows estimation of pest damage from the dual technology our estimates of aggregate u s pest damage are much lower than previous estimates

an evaluation of the swedish system of active labour market programmes in the 1990s we investigate the presence of short and long term effects from joining a swedish labor market program vis a vis more intense job search in open unemployment overall the impact of the program system is found to have been mixed joining a program has increased employment rates among participants a result robust to a misclassification problem in the data on the other hand it has also allowed participants to remain significantly longer on unemployment benefits and more generally in the unemployment system this being particularly the case for those entitled individuals entering a program around the time of their unemployment benefits exhaustion

search behaviour transitions to non participation and the duration of unemployment using longitudinal micro data on unemployed individuals for 1983 85 a structural job search model is estimated the model allows for transitions from unemployment to nonparticipation an extended version of the model deals with the influence of on the job search and prospective wage increases on search behavior of the unemployed the empirical results show that the probability of accepting a job offer is almost one for most unemployed individuals a large portion of unemployment spells ends in a transition out of the labor force the effects of changes in benefits on duration appear to be extremely small copyright 1990 by royal economic society

declining reservation wages and learning empirical studies of job search strongly suggest that the reservation wages of unemployed job seeking individuals decline with the length of their respective unemployment spells previous explanations of this behaviour based on age effects liquidity constraints and limited unemployment benefits are not adequate we provide a new answer to this question based on the reasonable assumption that workers do not have precise knowledge of the distribution of the prevailing wages an individual model of job search and learning is formulated it is shown that the declining trend of reservation wages naturally arises due to the selection process when search costs are not too small the example of a normal wage offer distribution is analysed and the implications are discussed

individual wealth reservation wages and transitions into employment we investigate the relationship between financial wealth reservation wages and labor market transitions wealth is assumed to affect the level of the reservation wage and the employment probability we test for the validity of this assumption by estimating a simultaneous equations model of reservation wages labor market transitions and wealth the data used for the analysis relate to a sample of unemployed job searchers we use subjective information on the reservation wage wealth is found to have a significantly positive impact on the reservation wage the overall impact of wealth on the employment probability is negative though small

selection of workers and firm heterogeneity a model based on differences between workers regarding their preferences for wage and leisure drives the heterogeneity of firms result the more industrious workers are driven to small firms due to free riding in large firms an industry consisting of small and large firms turns out to produce more output than an industry consisting of only large firms some comparative statics results are derived with respect to the size of large firms the productivity difference between firms and monitoring capabilities

off farm work and technical efficiency on u s dairies in this study we investigate the impact of an increase in farm households off farm work on technical efficiency te of u s dairies we present a theoretical framework that implies that an increase in farm household off farm work decreases te we use two nationally representative samples of u s dairies 2010 and 2005 agricultural resource management surveys and a parametric approach stochastic frontier analysis to empirically test the hypothesis results are generally consistent with the hypothesis and show that an increase in off farm work by the farm household is associated with a significant decrease in te in addition results show that there is a statistically significant difference in te between small medium and large farms small farms are associated with significantly higher off farm work and have lower te than large farms which implies that less off farm work by households with larger farms is at least partially responsible for the evidence of economies of scale in the u s dairy industry

unemployment duration and the restart effect some experimental evidence in this paper we analyse the effect of ihe restart programme in the united kingdom this programme consisis of an interview of tbe long term unemployed to counsel them on effective job search failure to attend the interview carries the threat of the cessation of unemployment benefits the results using experimental data indicate that the programme has a significant effect of reducing unemployment duration estimation of an independent competing risks model distinguishing between exits from unemployment to a job a training placement or to signing off unemployment benefit shows that the channels through which restart works differs according to exit type

biosecurity and disease management in china s animal agriculture sector abstract china s livestock production sector is changing rapidly to meet a variety of challenges the country is pursuing a major public animal health infrastructure upgrade and is seeking better integration with international public animal health programs the intent of this article is twofold we provide an overview of and commentary on china s animal husbandry sector and animal disease control policies we also assess weaknesses in its animal farm biosecurity infrastructure and institutional underpinnings china s animal health administration shares institutional weaknesses in common with higher income countries but her problems are more pronounced administrative failings include poorly demarcated and inconsistent oversight as well as weak accountability heterogeneous professional standards in animal health careers emphasis on quantity goals over qualitative metrics as well as a want in scientific analysis and follow through when prioritizing are other shortcomings spillovers from the general economy as well as government policies on animal health career professionalization and organization of animal sector production have been on the whole positive developments while animal production is changing in ways that may pose intermediate term threats to animal and human health the longer term outcome is likely to be a production base that poses fewer concerns for global health

risk attitudes and reservation wages of unemployed workers evidence from panel data abstract this paper studies risk attitudes of unemployed job seekers and their relationship to self reported reservation wages we find that risk aversion is prevalent and that reservation wages decrease slightly over time furthermore risk aversion and reservation wages are negatively correlated

an analysis of reservation wages for the economically inactive abstract data for the economically inactive are used to calculate elasticity estimates of the reservation wage and exit probability to state benefits and the arrival rate of job offers the inactive react in similar ways to benefit increases as the unemployed

the evolution of new industries and the determinants of market structure several empirical regularities concerning firm growth rates and industry firm size distributions have been developed by studying primarily mature industries the primary purpose of this article is to bring together and extend empirical regularities on the evolution of new industries and to use these regularities to gain further insight into the forces governing industry evolution to explain these regularities a model is constructed which emphasizes how factors governing the early evolution of industries may shape their market structure at maturity it stresses how chance events and exogenous factors that influence the number of potential entrants to the industry the growth rate of incumbents and the ease of imitation of industry leaders will influence the ultimate number and size distribution of firms in the industry

search models and applied labor economics individual effects in a nonlinear model explicit treatment of heterogeneity in the empirical job search model this paper extends the empirical version of a job search model to permit heterogeneity in the location of wage offer distributions population variance in wage offers is decomposed into variance due to heterogeneity and variance facing each individual heterogeneity is found to be an important source of offer variance in the population the amount of pure wage offer dispersion facing individuals is found to contribute little to population variance

should unemployment insurance vary with the unemployment rate theory and evidence we study how the marginal welfare gain from increasing the unemployment insurance ui bene t level varies over the business cycle we do this by estimating how the moral hazard cost and the consumption smoothing bene t of ui vary with labor market conditions which we identify using variation in the interaction of ui bene t levels with the unemployment rate within u s states over time we nd that the moral hazard cost is procyclical greater when the unemployment rate is relatively low by contrast we do not nd evidence that the consumption smoothing bene t varies with the unemployment rate we use these empirical results to estimate the marginal welfare gain and we nd that it is modest on average but varies positively with the unemployment rate jel h5 j64 j65

search for nonwage job characteristics a test of the reservation wage hypothesis previous structural models of job search behavior have been based upon the reservation wage property this article provides estimates of a more general search model that nests models with the reservation wage property the estimates lead to rejection of the reservation wage property the model includes hours of work in the utility function but other nonwage job characteristics can be included as well an experiment based on the estimated parameters indicates that a significant proportion of job offers would be mistakenly predicted to be accepted or rejected under the restrictions implied by the reservation wage property

real time search in the laboratory and the market the standard model of labor market search posits repeated infinite horizon search from a fixed distribution of wages in a stationary environment under these circumstances the optimal search policy has a reservation wage property i e the decision to accept an offer involves a comparison of the offer with a time invariant constant w which itself is a function of the parameters characterizing the search environment a wage offer greater than or equal to w is accepted while any other is rejected and search is continued some early empirical job search studies however accumulated evidence of a declining trend in reservation wages over the course of an unemployment spell 1 since then several theoretical explanations for the declining reservation wage profiles have emerged all of which relax the stationarity assumption of the standard model for example reuben gronau 1971 assumes searchers have finite lives kenneth burdett 1977 gerard j van den berg 1990 james albrecht and susan vroman 2005 and others model short term unemployment benefits albrecht pieter a gautier and vroman 2006 permit directed search to heterogeneous prospects 2 john p danforth 1979 and silvio rendon 2006 consider general liquidity con strained search and burdett and tara vishwanath 1988 model learning about the job offer distribution behavioral explanations for declining reservation wages have been suggested by braunstein and schotter 1981 schotter and braunstein 1982 and others in this paper we present the results of the first ever to our knowledge real time search laboratory experiment performed in an effort to investigate this falling res ervation wage phenomenon where field studies of unemployed search often rely on strong identifying assumptions to recover searchers unobservable reservation wages in the laboratory we are able to elicit subjects complete reservation wage profiles in an incentive compatible manner 3 further in the laboratory we are able to

prospective analysis of a wage subsidy for cape town youth abstract persistently high youth unemployment is one of the most pressing problems in south africa we prospectively analyze an employer wage subsidy targeted at youth a policy recently enacted by the south african government to address the issue recognizing that a credible estimate of the policy s impact requires a model of the labor market that itself generates high unemployment in equilibrium we estimate a structural search model that incorporates both observed heterogeneity and measurement error in wages using the model to simulate the policy we find that a r1000 month wage subsidy paid to employers leads to an increase of r596 in mean accepted wages and a decrease of 12 percentage points in the share of youth experiencing long term unemployment

on the use of expectations data in estimating structural dynamic choice models despite the importance of expectations in models of decision behavior under uncertainty few empirical economists have made use of subjective expectations data in estimating such models assuming that expectations about future behavior accurately portray optimal future behavior conditional on current information it is shown that such data can provide similar information about the decision process as can data on current or retrospective behavior the value of self reported choice expectations is illustrated by using information on respondents expected future occupation in the estimation of a structural dynamic model of teacher career decisions under uncertainty

the gender reservation wage gap evidence from british panel data abstract our findings suggest the existence of a gender reservation wage gap the presence of children particularly pre school age children plays an important role in determining the proportion of this gap that can be explained by individual characteristics

the reservation wage curve evidence from the uk we investigate the relationship between an individuals reservation wage and unemployment in the local area district largely unexplored in the literature this adds to the work which has examined the association between employee wages and unemployment the wage curve

cyclical variation in vacancy durations and vacancy flows an empirical analysis abstract this paper presents an empirical analysis of vacancy durations and vacancy flows in the netherlands over the years 1980 1988 we distinguish vacancies according to required occupation and educational levels we derive estimates of average vacancy durations and we use these to derive estimates of vacancy flows we find that vacancy durations generally increase with the required educational level moreover vacancy flows tend to be more responsive to the business cycle at lower educational levels while vacancy durations are more responsive at higher educational levels the number of vacancies generated by employers has not decreased during the recession in the early 80s which points to a dominant role of the supply of applicants in explaining the cyclical pattern of vacancy durations

the effect of active labor market programs on not yet treated unemployed individuals labor market programs may affect unemployed individuals behavior before they enroll such ex ante effects are hard to identify without model assumptions we develop a novel method that relates self reported perceived treatment rates and job search behavioral outcomes like the reservation wage to each other among newly unemployed workers job search theory is used to derive theoretical predictions to deal with effect heterogeneity and selectivity the effects of interest are estimated by propensity score matching we apply the method to the german active labor market program system using a novel data set including self reported assessments of the variables of interest as well as unusually detailed information on behavior attitudes and past outcomes we find that the system generates a negative ex ante effect on the reservation wage and a positive effect on search effort jel j64 c21 d83 d84

job separation in a non stationary search model a structural estimation to evaluate alternative unemployment insurance systems this paper considers a job search model in which the environment is not constant throughout the unemployment spell and where jobs do not last for ever in this situation reservation wages can be lower than they would be in a model without consideration of such separations but they can initially be higher precisely because of the non constant environment the model is estimated structurally by using spanish data for the period 1985 1996 the main finding is that after controlling for unobserved heterogeneity the unemployment hazard rate is almost flat during the first six months however after this duration the highly decreasing job offer arrival rate comes to be the only significant factor given that acceptance probabilities become equal to one the estimated parameters are used to evaluate different unemployment insurance designs we conclude that a non monotonic pattern in unemployment benefits joint with a tax paid by workers and based on unemployment duration makes this duration 13 2 lower than it currently is in spain copyright 2006 john wiley sons ltd

the information content of wage and duration data in a search model estimates of the parameters of the wage offer density and the offer arrival process of a simple search model are presented in this paper the optimality constraint from the search model is treated as a restriction and its effect on parameter estimates is analysed estimates from wage data alone and estimates from duration data alone can be interpreted as unrestricted estimates while estimates obtained from wage and duration data together can be interpreted as restricted estimates this interpretation allows a test of the optimality constraint which is rejected by the data used estimates reveal a substantial difference in the information contained in wages and the information contained in durations but benefit elasticities are consistent with findings from previous studies

unemployment benefit duration and incentives in britain how robust is the evidence abstract recent years have seen considerable advances in the econometric treatment of micro data in models of unemployment duration this paper examines the evidence from such models concerning the effects of unemployment benefits on incentives to work in britain widely accepted results of a small but significant benefit effect are reproduced using a sample of 1 231 unemployed men however these results are only found when benefit receipt is assumed to follow a hypothetical pattern which is shown to be unrealistic and over generous when more realistic calculations of benefits are used no benefit effect is found the paper also argues that search theory is of little help in determining the choice between competing functional forms and explanatory variables results concerning benefits are shown to be sensitive to the latter