Jon M. Conrad

Kennedy, John O. S. Dynamic Programming Applications to Agriculture and Natural Resources. London: Elsevier Applied Science Publishers, 1986, xv + 341 pp.,

I Introduction.- 1 The Management of Agricultural and Natural Resource Systems.- 1.1 The Nature of Agricultural and Natural Resource Problems.- 1.2 Management Techniques Applied to Resource Problems.- 1.2.1 Farm management.- 1.2.2 Forestry management.- 1.2.3 Fisheries management.- 1.3 Control Variables in Resource Management.- 1.3.1 Input decisions.- 1.3.2 Output decisions.- 1.3.3 Timing and replacement decisions.- 1.4 A Simple Derivation of the Conditions for Intertemporal Optimality.- 1.4.1 The general resource problem without replacement.- 1.4.2 The general resource problem with replacement.- 1.5 Numerical Dynamic Programming.- 1.5.1 Types of resource problem.- 1.5.2 Links with simulation.- 1.5.3 Solution procedures.- 1.5.4 Types of dynamic programming problem.- 1.6 References.- 1.A Appendix: A Lagrangian Derivation of the Discrete Maximum Principle.- 1.B Appendix: A Note on the Hamiltonian Used in Control Theory.- II The Methods of Dynamic Programming.- 2 Introduction to Dynamic Programming.- 2.1 Backward Recursion Applied to the General Resource Problem.- 2.2 The Principle of Optimality.- 2.3 The Structure of Dynamic Programming Problems.- 2.4 A Numerical Example.- 2.5 Forward Recursion and Stage Numbering.- 2.6 A Simple Crop-irrigation Problem.- 2.6.1 The formulation of the problem.- 2.6.2 The solution procedure.- 2.7 A General-Purpose Computer Program for Solving Dynamic Programming Problems.- 2.7.1 An introduction to the GPDP programs.- 2.7.2 Data entry using DPD.- 2.7.3 Using GPDP to solve the least-cost network problem.- 2.7.4 Using GPDP to solve the crop-irrigation problem.- 2.8 References.- 3 Stochastic and Infinite-Stage Dynamic Programming.- 3.1 Stochastic Dynamic Programming.- 3.1.1 Formulation of the stochastic problem.- 3.1.2 A stochastic crop-irrigation problem.- 3.2 Infinite-stage Dynamic Programming for Problems With Discounting.- 3.2.1 Formulation of the problem.- 3.2.2 Solution by value iteration.- 3.2.3 Solution by policy iteration.- 3.3 Infinite-stage Dynamic Programming for Problems Without Discounting.- 3.3.1 Formulation of the problem.- 3.3.2 Solution by value iteration.- 3.3.3 Solution by policy iteration.- 3.4 Solving Infinite-stage Problems in Practice.- 3.4.1 Applications to agriculture and natural resources.- 3.4.2 The infinite-stage crop-irrigation problem.- 3.4.3 Solution to the crop-irrigation problem with discounting.- 3.4.4 Solution to the crop-irrigation problem without discounting.- 3.5 Using GPDP to Solve Stochastic and Infinite-stage Problems.- 3.5.1 Stochastic problems.- 3.5.2 Infinite-stage problems.- 3.6 References.- 4 Extensions to the Basic Formulation.- 4.1 Linear Programming for Solving Stochastic, Infinite-stage Problems.- 4.1.1 Linear programming formulations of problems with discounting.- 4.1.2 Linear programming formulations of problems without discounting.- 4.2 Adaptive Dynamic Programming.- 4.3 Analytical Dynamic Programming.- 4.3.1 Deterministic, quadratic return, linear transformation problems.- 4.3.2 Stochastic, quadratic return, linear transformation problems.- 4.3.3 Other problems which can be solved analytically.- 4.4 Approximately Optimal Infinite-stage Solutions.- 4.5 Multiple Objectives.- 4.5.1 Multi-attribute utility.- 4.5.2 Risk.- 4.5.3 Problems involving players with conflicting objectives.- 4.6 Alternative Computational Methods.- 4.6.1 Approximating the value function in continuous form.- 4.6.2 Alternative dynamic programming structures.- 4.6.3 Successive approximations around a nominal control policy.- 4.6.4 Solving a sequence of problems of reduced dimension.- 4.6.5 The Lagrange multiplier method.- 4.7 Further Information on GPDP.- 4.7.1 The format for user-written data files.- 4.7.2 Redimensioning arrays in FDP and IDP.- 4.8. References.- 4.A Appendix: The Slope and Curvature of the Optimal Return Function Vi{xi}.- III Dynamic Programming Applications to Agriculture.- 5 Scheduling, Replacement and Inventory Management.- 5.1 Critical Path Analysis.- 5.1.1 A farm example.- 5.1.2 Solution using GPDP.- 5.1.3 Selected applications.- 5.2 Farm Investment Decisions.- 5.2.1 Optimal tractor replacement.- 5.2.2 Formulation of the problem without tax.- 5.2.3 Formulation of the problem with tax.- 5.2.4 Discussion.- 5.2.5 Selected applications.- 5.3 Buffer Stock Policies.- 5.3.1 Stochastic yields: planned production and demand constant.- 5.3.2 Stochastic yields and demand: planned production constant.- 5.3.3 Planned production a decision variable.- 5.3.4 Selected applications.- 5.4 References.- 6 Crop Management.- 6.1 The Crop Decision Problem.- 6.1.1 States.- 6.1.2 Stages.- 6.1.3 Returns.- 6.1.4 Decisions.- 6.2 Applications to Water Management.- 6.3 Applications to Pesticide Management.- 6.4 Applications to Crop Selection.- 6.5 Applications to Fertilizer Management.- 6.5.1 Optimal rules for single-period carryover functions.- 6.5.2 Optimal rules for a multiperiod carryover function.- 6.5.3 A numerical example.- 6.5.4 Extensions.- 6.6 References.- 7 Livestock Management.- 7.1 Livestock Decision Problems.- 7.2 Livestock Replacement Decisions.- 7.2.1 Types of problem.- 7.2.2 Applications to dairy cows.- 7.2.3 Periodic revision of estimated yield potential.- 7.3 Combined Feeding and Replacement Decisions.- 7.3.1 The optimal ration sequence: an example.- 7.3.2 Maximizing net returns per unit of time.- 7.3.3 Replacement a decision option.- 7.4 Extensions to the Combined Feeding and Replacement Problem.- 7.4.1 The number of livestock.- 7.4.2 Variable livestock prices.- 7.4.3 Stochastic livestock prices.- 7.4.4 Ration formulation systems.- 7.5 References.- 7.A Appendix: Yield Repeatability and Adaptive Dynamic Programming.- 7.A.1 The concept of yield repeatability.- 7.A.2 Repeatability of average yield.- 7.A.3 Expected yield given average individual and herd yields.- 7.A.4 Yield probabilities conditional on recorded average yields.- IV Dynamic Programming Applications to Natural Resources.- 8 Land Management.- 8.1 The Theory of Exhaustible Resources.- 8.1.1 The simple theory of the mine.- 8.1.2 Risky possession and risk aversion.- 8.1.3 Exploration.- 8.2 A Pollution Problem.- 8.2.1 Pollution as a stock variable.- 8.2.2 A numerical example.- 8.3 Rules for Making Irreversible Decisions Under Uncertainty.- 8.3.1 Irreversible decisions and quasi-option value.- 8.3.2 A numerical example.- 8.3.3 The discounting procedure.- 8.4 References.- 9 Forestry Management.- 9.1 Problems in Forestry Management.- 9.2 The Optimal Rotation Period.- 9.2.1 Deterministic problems.- 9.2.2 Stochastic problems.- 9.2.3 A numerical example of a combined rotation and protection problem.- 9.3 The Optimal Rotation and Thinning Problem.- 9.3.1 Stage intervals.- 9.3.2 State variables.- 9.3.3 Decision variables.- 9.3.4 Objective function.- 9.4 Extensions.- 9.4.1 Allowance for distributions of tree sizes and ages.- 9.4.2 Alternative objectives.- 9.5 References.- 10 Fisheries Management.- 10.1 The Management Problem.- 10.2 Modelling Approaches.- 10.2.1 Stock dynamics.- 10.2.2 Stage return.- 10.2.3 Developments in analytical modelling.- 10.3 Analytical Dynamic Programming Approaches.- 10.3.1 Deterministic results.- 10.3.2 Stochastic results.- 10.4 Numerical Dynamic Programming Applications.- 10.4.1 An application to the southern bluefin tuna fishery.- 10.4.2 A review of applications.- 10.5 References.- V Conclusion.- 11 The Scope for Dynamic Programming Applied to Resource Management.- 11.1 Dynamic Programming as a Method of Conceptualizing Resource Problems.- 11.2 Dynamic Programming as a Solution Technique.- 11.3 Applications to Date.- 11.4 Expected Developments.- 11.5 References.- Appendices.- A1 Coding Sheets for Entering Data Using DPD.- A2 Program Listings.- A2.1 Listing of DPD.- A2.2 Listing of FDP.- A2.3 Listing of IDP.- A2.4 Listing of DIM.- Author Index.

76.00

Abstract The option value of an old-growth forest is determined when the net value of timber is known and non-timber amenity value evolves according to geometric Brownian motion. The model permits the derivation of a critical barrier or boundary on amenity value, denoted A*. Specifically, A* is the minimum amenity value necessary to justify continued preservation. The model is applied to the Headwaters Forest, the last privately-owned stand of old-growth coast redwood, containing timber with a net value between

On the option value of old-growth forest

500 and

Wilderness: options to preserve, extract, or develop

600 million. Estimates of the mean drift and variance rates for the amenity value of the headwaters are obtained under the assumption that amenity value is proportional to the visitation rate at the Redwood National Park (50 miles north of the Headwaters Forest). For base-case parameters, the amenity value of the Headwaters must exceed

Managing Urban Deer

5.008 million per year to justify continued preservation.

Capital Dynamics in the North Sea Herring Fishery

Option-pricing is used to evaluate the sequence and timing of wilderness preservation, resource extraction, and development. Resource extraction or development results in the permanent destruction of wilderness and the loss of an amenity dividend. Resource extraction does not preclude subsequent development. If the wilderness is directly developed (without prior extraction of resources), wilderness and resource extraction options are both killed. Starting from a state of wilderness, there are two stochastically evolving barriers, one for the price of the resource, and the other for the return on development. Wilderness is preserved provided the price of the resource never catches the price barrier and the return on development never catches the return barrier.

Open access harvesting of the Northeast Atlantic minke whale

Conflicts are emerging between humans and wildlife populations adaptable to the high density of humans found in urban and suburban areas. In response to these threats, animal control programs are typically designed with the objective of establishing and maintaining a stable population. This article challenges this view by studying the management of urban deer in Irondequoit, NY. Pulsing controls can be more efficient than steady-state regimes under a wide range of conditions in both deterministic and stochastic environments, but potential gains can be dissipated by management constraints. The effect of citizen opposition to lethal control methods is also investigated.

Optimizing the Riparian Buffer: Harold Brook in the Skaneateles Lake Watershed, New York

Dynamic adjustment is an integral part of natural resource economics. Commonly, capital is assumed to respond instantaneously to changes in profits, while in reality adjustment may take place only with a time lag. In this paper, an empirical analysis of capital (boat) dynamics in the North Sea herring fishery is undertaken. A discrete time model is formulated to model decisions of boats to enter or exit the fishery. A lagged model is specified to reflect adjustment time to changes in profits. The empirical results indicate that fleet adjustment in this fishery primarily depends on current period profits and that the opportunity cost may depend on returns in the alternative fishery. Inclusion of lagged variables to account for the construction time for new boats, showed only a small improvement in the statistical fit. Moreover, the results did not support a hypothesis that entry in response to positive profits is more elastic than exit due to negative profits.

The Economics Of A Stock Pollutant: Aldicarb On Long Island

The purpose of this paper is to analyze open access exploitation of the Northeast Atlantic minke whale. In particular the question whether open access could lead to stock extinction is addressed. A bioeconomic model of the open access fishery is developed and estimated for data from Norwegian whaling. Numerical analysis shows that open access was not likely to have lead to stock extinction for the minke whale.

A Plant-Level, Spatial, Bioeconomic Model of Plant Disease Diffusion and Control: Grapevine Leafroll Disease

The use of riparian land buffers to protect water quality for human consumption and wildlife habitat has become an important conservation tool of both government and non-government agencies. The funds available to acquire private lands for riparian buffers are limited, however, and not all land contributes to water quality goals in the same way. Conservation agencies must therefore identify effective ways to allocate their scarce budgets in heterogeneous landscapes. We demonstrate how the acquisition of land for a riparian buffer can be viewed as a binary optimization problem and we apply the resulting model to a case study in New York. (JEL Q15, Q25)