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Preface | |
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Acknowledgments | |
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Introduction | |
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Common-sense solutions: three exercises | |
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Modeling theory | |
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Modeling practice | |
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Theory, practice, and common sense | |
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Intended use of this book | |
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Common-sense solutions: three exercises | |
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Common-sense solutions | |
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Three problems | |
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Harvesting food for the winter | |
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Estimating the probability of population extinction | |
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Managing the Commons | |
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The systems approach to problem solving | |
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The conceptual model (Phase I) | |
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The quantitative model (Phase II) | |
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Model evaluation (Phase III) | |
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Model application (Phase IV) | |
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The three problems revisited: the systems approach in theory and practice | |
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Modeling theory | |
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Theory I: the conceptual model | |
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State the model objectives (I[subscript a]) | |
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Bound the system-of-interest (I[subscript b]) | |
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Categorize the components within the system-of-interest (I[subscript c]) | |
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State variables | |
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Material transfers | |
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Sources and sinks | |
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Information transfers | |
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Driving variables | |
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Constants | |
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Auxiliary variables | |
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Identify the relationships among the components that are of interest (I[subscript d]) | |
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Submodels | |
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Represent the conceptual model (I[subscript e]) | |
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Conceptual-model diagrams | |
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Describe the expected patterns of model behavior (I[subscript f]) | |
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Theory II: the quantitative model | |
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Select the general quantitative structure for the model (II[subscript a]) | |
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Choose the basic time unit for the simulations (II[subscript b]) | |
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Identify the functional forms of the model equations (II[subscript c]) | |
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Information on which to base the choice of functional forms | |
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Selecting types of equations to represent the chosen functional forms | |
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Estimate the parameters of the model equations (II[subscript d]) | |
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Statistical analyses within the context of simulation model parameterization | |
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Quantifying qualitative information | |
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Deterministic- versus stochastic-model parameterization | |
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Execute the baseline simulation (II[subscript e]) | |
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Baseline simulations for stochastic models | |
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Theory III: model evaluation | |
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Assess the reasonableness of the model structure and the interpretability of functional relationships within the model (III[subscript a]) | |
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Evaluate the correspondence between model behavior and the expected patterns of model behavior (III[subscript b]) | |
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Examine the correspondence between model projections and the data from the real system (III[subscript c]) | |
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Quantitative versus qualitative model evaluation | |
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Determine the sensitivity of model projections to changes in the values of important parameters (III[subscript d]) | |
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Interpreting sensitivity analysis within a model evaluation framework | |
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Theory IV: model application | |
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Develop and execute the experimental design for the simulations (IV[subscript a]) | |
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Analyze and interpret the simulation results (IV[subscript b]) | |
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Communicate the simulation results (IV[subscript c]) | |
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Modeling practice | |
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Some common pitfalls | |
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Phase I pitfalls: the conceptual model | |
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Phase II pitfalls: the quantitative model | |
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Phase III pitfalls: model evaluation | |
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Phase IV pitfalls: model application | |
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The modeling process in practice | |
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Preliminary conceptual model (CM) | |
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How to begin | |
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Adding new components to the model | |
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Describing expected patterns | |
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Describing the plan of attack | |
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Intermediate developmental models (IDM[subscript i]) | |
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Evaluate-adjust cycle for each developmental model | |
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Sensitivity analysis of the last developmental model | |
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Final model (FM) | |
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Theory, practice, and common sense | |
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The common-sense problems revisted | |
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Harvesting food for the winter | |
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The preliminary conceptual model (CM) | |
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The last (only) intermediate development model (IDM[subscript last]) | |
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The final model (FM) | |
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Estimating the probability of population extinction | |
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The preliminary conceptual model (CM) | |
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The intermediate development models (IDM[subscript i]) | |
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The final model (FM) | |
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Managing the Commons | |
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The preliminary conceptual model (CM) | |
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The intermediate development models (IDM[subscript i]) | |
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The final model (FM) | |
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Reflections | |
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The systems approach as a complement to other methods of problem solving | |
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Ecological modeling as a problem-solving process | |
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Expectations for ecological models | |
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A final thought | |
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References | |
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Introduction to the ecological modeling literature | |
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Scientific reports for the examples in Chapter 2 | |
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Effect of deforestation on rate of food harvest | |
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Effect of hurricane frequency on probability of population extinction | |
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Effect of stocking rate on forage and animal production | |
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Index | |