SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Cacho, Oscar J.; Jones, Randall E..

It is argued in this paper that static approaches to weed management, where the benefits and costs are only considered within a single season, are inappropriate for assessing the economic benefits of weed control technologies. There are carryover effects from weed management as weeds that escape control in one season may reproduce and replenish weed populations in following seasons. Consequently, it is appropriate to view weed control in the context of a resource management problem where the goal is to determine the optimal inter-temporal level of weed control that maximises economic benefits over some pre-determined period of time. A dynamic optimisation model for weed control is presented. Using the tools of comparative static analysis and Pontryagin's...

Accounting for agronomic rotations in crop production: A theoretical investigation and an empirical modeling framework

Palavras-chave: Weed control; Resource economics; Optimal control; Dynamic programming; Wild oats; Farm Management.

Ano: 2000

URL: http://purl.umn.edu/12902

Carpentier, Alain; Gohin, Alexandre; Letort, Elodie.

As far as crop acreage choices are concerned, a consensus seems to exist among agricultural scientists and extension agents: crop rotation effects and the related constraints are major determinants of farmers’ crop choices. Crop rotation effects are inherently dynamic. They are generally ignored in multicrop models with land as an allocable input found in the literature since most of these models are developed within a static framework. The aim of this paper is twofold (i) to propose a new approach and tools for investigating dynamic crop acreage choices accounting for crop rotation benefits and constraints and (ii) to illustrate the impacts of crop rotation effects and constraints on farmers’ acreage choices through simulation examples. The models...

An Economic Analysis of Water Infrastructure Investments, Agricultural Productivity and Climate Change in the Mekong Delta: Adapting to Increased Salinity and Sea Level Rise

Palavras-chave: Crop rotation; Dynamic programming; Acreage choice; Crop Production/Industries; Land Economics/Use; Q12; D21; D24; D92.

Ano: 2011

URL: http://purl.umn.edu/103431

Corderi Novoa, David; Williams, Jeffrey C.; Howitt, Richard E.; Lund, Jay R..

Replaced with revised version of paper 07/24/11.

An Incentive System for Salmonella Control in the Pork Supply Chain

Palavras-chave: Climate change; Adaptation; Agriculture; Water resources; Dynamic programming; Crop Production/Industries; Environmental Economics and Policy; International Development; Production Economics; Risk and Uncertainty; Q54; Q25; Q15.

Ano: 2011

URL: http://purl.umn.edu/103875

Backus, Ge B.C.; King, Robert P..

This paper presents a dynamic principal-agent analysis of an incentive system for Salmonella control in the pork supply chain. The incentive system determines quality premiums to the producer, testing frequencies for hogs delivered, as well as charges to the producer for testing and penalties. Using cost estimates and technical parameters, we evaluate the cost effectiveness of plant and farm control measures and trade-offs between prevalence reduction and related costs and gains. We also assess the impact of ownership structure on incentive system parameters and performance for a wide range of prevalence threshold levels. Differences in control actions, bacteriological prevalence and the overall welfare gain for the chain are very small across ownership...

Bioeconomic meta-modelling of Indonesian agroforests as carbon sinks

Palavras-chave: Dynamic programming; Food quality; Principal-agent; Food Consumption/Nutrition/Food Safety; Livestock Production/Industries.

Ano: 2007

URL: http://purl.umn.edu/9941

Wise, Russell M.; Cacho, Oscar J..

In many areas of developing countries, economic and institutional factors often combine to give farmers incentives to clear forests and repeatedly plant food crops without sufficiently replenishing the soils. These activities lead to large-scale land degradation and contribute to global warming through the release of greenhouse gases into the atmosphere. We investigate whether agroforestry systems might alleviate these trends when carbon-credit payments are available under the Clean Development Mechanism of the Kyoto Protocol. A meta-modelling framework is adopted, comprising an econometric-production model of a smallholding in Sumatra. The model is used within a dynamic-programming algorithm to determine optimal combinations of tree/crop area,...

DEVELOPING FLEXIBLE ECONOMIC THRESHOLDS FOR PEST MANAGEMENT USING DYNAMIC PROGRAMMING

Palavras-chave: Bio-economic meta-modelling; Indonesia; Agroforestry; Carbon credits; Dynamic programming; Environmental Economics and Policy; Resource /Energy Economics and Policy.

Ano: 2008

URL: http://purl.umn.edu/6772

Harper, Jayson K.; Mjelde, James W.; Rister, M. Edward; Way, Michael O.; Drees, Bastiaan M..

The rice stink bug is a major pest of rice in Texas, causing quality related damage. The previous threshold used for assisting in rice stink bug spray decisions lacked flexibility in economic and production decision variables and neglected the dynamics of the pest population. Using stochastic dynamic programming, flexible economic thresholds for the rice stink bug were generated. The new thresholds offer several advantages over the old, static thresholds, including increased net returns, incorporation of pest dynamics, user flexibility, ease of implementation, and a systematic process for updating.

Tipo: Journal Article

Palavras-chave: Economic thresholds; Dynamic programming; Pest management; Rice; Crop Production/Industries.

Ano: 1994

URL: http://purl.umn.edu/15411

Die Berücksichtigung von Unsicherheit und Flexibilität in der Investitionsplanung – dargestellt am Beispiel einer Vertragsinvestition für Roggen

Musshoff, Oliver; Hirschauer, Norbert.

Investment decisions are, as a rule, characterized by uncertainty, irreversibility and flexibility. Simple net present value calculations will not account for these features. In many situations even flexible investment planning with decision trees, which represents the most advanced method of traditional investment appraisal, does not have the capacity to solve practical decision problems adequately. One handicap is a realistic and manageable representation of stochastic variables. It has long been known that stochastic simulation procedures offer a nearly unlimited capacity to represent distributions and stochastic processes. However, a standard simulation will not allow for the consideration of flexibility. The problem is that with a simple forward...

Tipo: Journal Article

Palavras-chave: Investment; Uncertainty; Flexibility; Stochastic simulation; Dynamic programming; Sales contracts with fixed prices; Farm Management; Research Methods/ Statistical Methods; Risk and Uncertainty.

Ano: 2004

URL: http://purl.umn.edu/97437

Dynamic Time Warping of Paleomagnetic Secular Variation Data

ArchiMer

Hagen, Cedric J; Reilly, Brendan T; Stoner, Joseph S; Creveling, Jessica R.

We present and make publicly available a dynamic programming algorithm to simultaneously align the inclination and declination vector directions of sedimentary paleomagnetic secular variation data.This algorithmgenerates a library of possible alignments through the systematic variation of assumptions about the relative accumulation rate and shared temporal overlap of two or more time-series. The paleomagnetist can then evaluate this library of reproducible and objective alignments using available geologic constraints, statistical methods, and expert knowledge.We apply the algorithm to align previously (visually) correlated medium to high accumulation rate northern North Atlantic Holocene deposits (101– 102 cm/ka) with strong radiocarbon control. The...

Tipo: Text

Palavras-chave: Palaeomagnetic secular variation; Palaeomagnetism; Magnetostratigraphy; Dynamic programming; Statistical methods; Atlantic Ocean.

Ano: 2020

URL: https://archimer.ifremer.fr/doc/00601/71322/69749.pdf

Dynamically Optimal Phosphorus Management and Agricultural Water Protection

Iho, Antti; Laukkanen, Marita.

This paper puts forward a model of the role of phosphorus in crop production, soil phosphorus dynamics and phosphorus loading that integrates the salient economic and ecological features of agricultural phosphorus management. The model accounts for the links between phosphorus fertilization, crop yield, accumulation of soil phosphorus reserves, and phosphorus loading. It can be used to guide precision phosphorus management and erosion control as means to mitigate agricultural loading. Using a parameterization for cereal production in southern Finland, the model is solved numerically to analyze the intertemporally optimal combination of fertilization and erosion control and the associated soil phosphorus development. The optimal fertilizer application rate...

Dynamics of Phosphorus Fertilization and Liming Under Land Tenure Insecurity

Palavras-chave: Precision nutrient management; Agricultural phosphorus loading; Cereal production; Soil phosphorus reserves; Agricultural water pollution; Dynamic programming; Agricultural and Food Policy; Crop Production/Industries; Environmental Economics and Policy.

Ano: 2009

URL: http://purl.umn.edu/54285

Myyra, Sami; Pietola, Kyosti.

This article solves and characterizes optimal decision rules to invest in irreversible land improvements conditional on land tenure insecurity. Economic model is a normative dynamic programming model with known parameter for the one period returns and transition equations. The decision rules are solved numerically conditional on alternative scenarios on the likelihood that the lease contract and, thus, farmer access to land is either renewed or expires. The model parameters represent Finnish soil quality and production conditions. The results suggest that irreversible land improvements decrease quickly and the yields decline gradually when the farmer is confronted with land tenure insecurity caused by uncertain renewal of the lease contract.

Economic cost of environmental flows in an unregulated river system

Palavras-chave: Agriculture; Dynamic programming; Land Economics/Use; Q15; Q21.

Ano: 2005

URL: http://purl.umn.edu/24633

Jones, Randall E.; Crean, Jason; Aluwihare, Parakrama B.; Letcher, Rebecca A..

This paper applies a stochastic dynamic programming framework, incorporating links to hydrological and biophysical models, to assess the economic costs of environmental flows in an unregulated river system in the Namoi Valley of northern New South Wales, Australia. Structural adjustment decisions are included in the model to account for farmer responses to changes in environmental flows through the introduction of a water sharing plan. The results of the analysis indicate that the proposed level of environmental flows reduces water extractions by around 6 per cent, and imposes an opportunity cost of less than 1 per cent in terms of reduced net income over a 20-year period.

Tipo: Journal Article

Palavras-chave: Dynamic programming; Environmental flows; Irrigation; Resource /Energy Economics and Policy.

Ano: 2007

URL: http://purl.umn.edu/118334

Exploring long-term land improvements under land tenure insecurity

Myyra, Sami; Pietola, Kyosti.

This article explores long-term land improvement (lime application) under land tenure insecurity on leased land. The dynamic optimisation problem is solved by a stochastic dynamic programming routine with known parameters for one-period returns and transition equations. The model parameters represent Finnish soil quality and production conditions. The farmer's decision rules are solved for alternative likelihood scenarios over the continuation of the fixed term lease contract. The results suggest that, as the probability for non-renewal of the lease contract increases, farmers quickly decrease investments in irreversible land improvement and, thereafter, yields decline gradually. The estimated decision rules are a part of larger set of farmer's decision...

Farmers' Exit Decisions and Early Retirement Programs in Finland

Palavras-chave: Dynamic programming; Land tenure; Land improvements; Land Economics/Use.

Ano: 2006

URL: http://purl.umn.edu/31954

Pietola, Kyosti; Vare, Minna; Oude Lansink, Alfons G.J.M..

This paper estimates farmer decisions between three discrete occupational choices: exit and close down the farming operation (1), exit and transfer the farm to a new entrant (2), or continue farming and retain the option to exit later on (3). The farmer optimisation problem is formulated as a recursive optimal stopping problem. The unknown parameters are first estimated by a switching-type, reduced form Probit models and, then by the Simulated maximum likelihood (SML) method, controlling for serial correlation in the errors. Serial correlation in the errors is controlled for by the Geweke-Hajivassiliou-Keane (GHK) simulation technique. The results suggest that the timing and the type of farmer exit decisions respond elastically to farmer characteristics,...

Ground Water Quantity and Quality Management: Agricultural Production and Aquifer Salinization over Long Time Scales

Palavras-chave: Exit; Entry; Dynamic programming; Switching-type Probit; Simulated Maximum Likelihood; Labor and Human Capital.

Ano: 2002

URL: http://purl.umn.edu/24825

Knapp, Keith C.; Baerenklau, Kenneth A..

An economic model of ground water salinization is developed. Starting from a full, high-quality aquifer, there is an initial extraction period, an intermediate waste disposal period, and a final drainage period. Drainage management is initially source control and reuse, but eventually culminates in evaporation basins and a system steady-state. This process occurs over long time scales but is consistent with historical observation. Efficiency is qualitatively similar to common property though quantitative magnitudes differ substantially. Regulatory pricing instruments are developed to support the efficient allocation. The system is not sustainable in that net returns generally decline through time until the steady-state.

Tipo: Journal Article

Palavras-chave: Common property; Dynamic programming; Efficiency; Ground water; Irrigation; Salinity; Sustainability; Resource /Energy Economics and Policy.

Ano: 2006

URL: http://purl.umn.edu/8633

Insure or Invest in Green Technologies to Protect Against Adverse Weather Events?

Pietola, Kyosti; Myyra, Sami; Niemi, Jarkko K.; Van Asseldonk, Marcel A.P.M..

This paper analyses investments in green technologies when insurance is also an option. Green technologies are defined to have the power to increase productivity and decrease volatility of future revenues. The insurance options involve the scale and coverage either in a yield insurance or in an index insurance. The stochastic process is a combination of insurable stationary short-run process and non-stationary long run process. The optimal decision rules are solved numerically by stochastic dynamic programming. The results suggest that the index insurance maintains market based incentives to invest in green technologies whereas a yield insurance substantially decreases investments, as expected. An actuarially fair yield insurance decreases investments at...

Investment planning under uncertainty and flexibility: the case of a purchasable sales contract

Palavras-chave: Investment; Insurance; Uncertainty; Dynamic programming; Green technology; Agribusiness; Agricultural Finance; Financial Economics; Risk and Uncertainty.

Ano: 2011

URL: http://purl.umn.edu/100738

Musshoff, Oliver; Hirschauer, Norbert.

Investment decisions are not only characterised by irreversibility and uncertainty but also by flexibility with regard to the timing of the investment. This paper describes how stochastic simulation can be successfully integrated into a backward recursive programming approach in the context of flexible investment planning. We apply this hybrid approach to a marketing question from primary production which can be viewed as an investment problem: should grain farmers purchase sales contracts which guarantee fixed product prices over the next 10 years? The model results support the conclusion from dynamic investment theory that it is essential to take simultaneously account of uncertainty and flexibility.

Tipo: Journal Article

Palavras-chave: Dynamic programming; Flexibility; Investment; Sales contract; Stochastic simulation; Uncertainty; Agricultural Finance; Risk and Uncertainty.

Ano: 2008

URL: http://purl.umn.edu/117741

LONG-TERM PLANNING OF A LIVESTOCK-CROP FARM UNDER GOVERNMENT PROGRAMS

Kouka, Pierre-Justin; Duffy, Patricia A.; Taylor, C. Robert.

Optimal crop and livestock mix was determined for a representative Alabama farm using a dynamic programming model. Results indicate that decisions concerning livestock production are highly influenced by the amount of cotton base available on the farm. In most cases, increasing cotton base results in less cattle production. The triple base provisions of the 1990 Farm Bill, however, may give some cotton farmers an incentive to produce more stocker cattle during the winter months. Research results also indicate that the availability of farm programs can alter the optimal enterprise mix on a farm with no beginning base in cotton.

Tipo: Journal Article

Palavras-chave: Farm programs; Dynamic programming; Livestock; Farm Management.

Ano: 1994

URL: http://purl.umn.edu/15407

Market implications of FMD epidemics in the Finnish pig sector: Does market structure matter?

Niemi, Jarkko K.; Lehtonen, Heikki; Lyytikainen, Tapani; Kallio, E..

This paper examines the role of market coordination and market distortions caused by a hypothetical FMD outbreak in the Finnish pig sector. By using stochastic dynamic programming, it simulates the consequences of two outbreak scenarios (large vs. small) under two distinct market regimes (competitive market vs. monopoly in the domestic supply). Simulated losses depend on the magnitude of outbreak and expected duration of possible turndown of meat exports, whereas market regime has a limited impact.

MODELLING THE DYNAMICS OF PRODUCTION ADJUSTMENT TO SHORT-TERM MARKET SHOCKS

Palavras-chave: Foreign trade; Livestock epidemics; Dynamic programming; Livestock Production/Industries.

Ano: 2008

URL: http://purl.umn.edu/43837

Niemi, Jarkko K.; Lehtonen, Heikki.

Models of agricultural economics typically operate at an annual basis or in a static equilibrium framework where inputs, outputs and their prices may change considerably. Production dynamics, however, imply that models relying on spatial and temporal aggregation do not capture the effects of biological constraints in the short run. This paper examines short and long-term impacts of demand and production cost shocks in the pig sector. The analysis is carried out with a dynamic programming model which takes into account changes in export and domestic demand and market clearing price. It optimizes the supply of piglets on a monthly basis. Econometric techniques are used to estimate demand functions. Short-term negative market shocks can already have...

On the Potential Use of Adaptive Control Methods for Improving Adaptive Natural Resource Management

Palavras-chave: Pig; Demand; Dynamic programming; Export; Livestock epidemics; Price; Supply; Demand and Price Analysis; Livestock Production/Industries; Production Economics; Risk and Uncertainty.

Ano: 2008

URL: http://purl.umn.edu/6401

Bond, Craig A..

The paradigm of adaptive natural resource management (AM), in which experiments are used to learn about uncertain aspects of natural systems, is gaining prominence as the preferred technique for administration of large-scale environmental projects. To date, however, tools consistent with economic theory have yet to be used to either evaluate AM strategies or improve decision-making in this framework. Adaptive control (AC) techniques provide such an opportunity. This paper demonstrates the conceptual link between AC methods, the alternative treatment of realized information during a planning horizon, and AM practices; shows how the different assumptions about the treatment of observational information can be represented through alternative dynamic...