Optimisation models are a key tool for the analysis of emerging policies, price sets, and technologies within grazing systems. A detailed nonlinear optimisation model of a New Zealand dairy farming system is described. The framework is notable for its rich portrayal of pasture and cow biology...

Environmental policy evaluation is characterised by a paucity of information. Bounded sets may be more appropriate for representing this ambiguity than traditional probability distributions. A formal calibration method for regional policy models, positive mathematical programming, is thus...

The increasing prevalence of anthelmintic (drench) resistance in gastrointestinal parasite populations is decreasing the profitability of the sheep industry in Western Australia (WA). A strategy, referred to as refugia management, has the potential to delay the development of resistant parasites...

Many important problems in agricultural and natural resource economics concern an intertemporal choice between alternate dynamic systems. This significance has motivated a theoretical literature generalizing the necessary conditions of Optimal Control Theory to multiple-phase problems. However,...

This short paper provides a simple introduction on how a simulation model implemented in Microsoft Excel® can be optimised using Visual Basic for Applications (VBA) programming and the compressed simulated annealing algorithm (Ohlmann et al., 2004; Ohlmann and Thomas, 2007). The standard simulated...

Implications of increasing labour cost and development of herbicide resistance for profitable weed management in Philippine rice farming systems are investigated. The study employs RIMPhil (Resistance and Integrated Management in the Philippines), a bioeconomic simulation model developed to...

This study involves the application of a random-effects double-hurdle model to survey data to identify the farm-level factors affecting the adoption and intensity of herbicide use in rice production in the Philippines. Results broadly indicate apparent differences in the degree to which...

This paper describes a complex, dynamic simulation model that has been developed for the analysis of integrated weed management programmes for the control of annual barnyardgrass (Echinochloa crus-galli) in rice farming systems in the Philippines. Users of the model may simulate any feasible...

Annual recruitment of the NewZealand longfin eel (Anguilla dieffenbachii) hasdecreased by 75 per cent since significant levels of commercial fishing began in the early 1970s. This motivates application of a multiple-cohort bioeconomic model to a New Zealand longfin eel fishery to investigate its...

The capacity of global agricultural production to meet increased demand for food from population growth and wealth accumulation is threatened by extensive land degradation. Nonetheless, previous research has focused primarily on the dynamic implications of input management and ignored land-use...