GIS models are powerful tools for analyzing spatial data and solving complex problems. However, they are not infallible and can produce erroneous or misleading results if not checked properly. In this article, you will learn some basic steps to check your GIS models and ensure their validity and reliability.
The first step to check your GIS models is to define your model objectives clearly and explicitly. What are you trying to achieve with your model? What are the main questions or hypotheses you want to answer or test? What are the expected outputs and outcomes of your model? By defining your model objectives, you can set the scope and criteria for your model design, data selection, analysis methods, and evaluation measures.
The second step to check your GIS models is to choose appropriate data and methods for your model objectives. You should select data that are relevant, accurate, consistent, and complete for your spatial analysis. You should also choose methods that are suitable, robust, and transparent for your model objectives. You should document your data sources, methods, and assumptions, and justify your choices with references or evidence.
The third step to check your GIS models is to test your model performance and identify any errors or issues. You should run your model with different inputs, parameters, and scenarios, and compare the results with expected or observed values. You should also check for any logical, syntactical, or computational errors in your model structure, code, or output. You should use tools such as error messages, logs, debuggers, or breakpoints to troubleshoot your model and fix any problems.
The fourth step to check your GIS models is to evaluate your model results and assess their quality and significance. You should use quantitative and qualitative methods to measure your model accuracy, precision, sensitivity, uncertainty, and validity. You should also use graphical and statistical methods to visualize, summarize, and interpret your model results. You should report your model results with clear and concise descriptions, tables, charts, maps, or diagrams.
The fifth step to check your GIS models is to compare your model with alternative models and methods. You should review the literature and existing models that address similar objectives or questions as yours. You should also explore different ways to design, implement, or run your model, and see how they affect your results. You should compare your model with alternatives in terms of their advantages, disadvantages, limitations, and assumptions.
The final step to check your GIS models is to communicate your model findings and implications to your audience. You should tailor your communication style, format, and language to suit your audience's needs, expectations, and background. You should also provide clear and honest explanations of your model objectives, data, methods, results, evaluation, and comparison. You should highlight the main points, insights, and recommendations of your model, and acknowledge any uncertainties, limitations, or challenges.