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Custom Modelling

whatIf? Technologies specializes in the design and implementation of custom systems models using methods, standards and procedures supported by the whatIf?® software technology. The following five stages are typical of a custom modelling project:

1. Design Workshop

In this first stage our model designers come together with the client to scope and design the model, along with subject matter experts and data holdings experts. First, scoping establishes the issues that the model will be used to analyze. This is followed by model design - identifying processes to be represented in the model, and defining the relationships among these processes. Also considered at this stage are critical uncertainties which become the subject of exploratory simulation; and identification of data sources.

Resulting from the design phase are two types of diagrams: high-level, hierarchical diagrams that organize the model into components; and low-level structural diagrams of each component. The diagrams are created interactively during the workshop using the whatIf? Documenter software, and feed seamlessly into the coding and scenario-building activities that follow.

The design workshop recognizes that much of the information required to build a model is "stored" tacitly in the minds of those familiar with the system in question. Furthermore, the purpose for, or issues behind a model must be made clear by the stakeholders before the model's construction. The approach here is not "give us your files and we'll build you a model". The workshop draws out information from stakeholders and experts, and puts it in a framework - the model - designed to explore particular issues.

2. Model Coding

The diagrams produced in the design workshop represent processes within the system being modelled, and also the relationships amongst these processes. During the coding phase, these relationships are made explicit and formalized - that is, their logic coded in the whatIf? TOOL language. The coding phase also provides an opportunity to begin training clients wishing to learn the TOOL language - the same language used to implement data import and reporting functionality after the model's initial release.

3. Calibration and Data Assembly

Models are calibrated over historical time to assure that model results are consistent with observed data. Calibration results in the assembly of a complete set of historical values of all a model's variables that are consistent with the necessary relationships of the model. Calibration involves assembly of the data sets identified in the design phase, conversion and standardization, parameter estimation, and estimation of missing data.

Calibration is accomplished using the whatIf? Documenter software for the implementation of a formal calibration model - distinct from the simulation model for the end user. The calibration model takes as input raw data files and represents the procedures for transforming them into a complete and coherent set of historical data in such a way that the logic of the simulation model can be run over the historical period. The output of the calibrator is linked to the simulator in such a way that historical data can be seen from the simulator. Consequently, the development of the calibration model is usually a larger and more complex task than creating the simulator.

4. Scenario Workshop

In the scenario workshop our model designers and facilitators meet with the client to begin exploring the future using the model, via scenario creation and analysis.

Scenarios are possible pathways into the future, possible in that they are internally consistent and anchored in the present. To be effective, scenarios should reflect different ways of seeing the world, not just "high" and "low" forecasts. They should focus on critical uncertainties and illuminate the major forces driving the system and the interrelationships among them.

Workshops provide an environment for focusing and sustaining the creative energy and expertise of the people that are essential in strategic planning and policy formulation. The prerequisite for a successful scenario analysis workshop is a decision support framework that is accepted by the stakeholders as an adequate representation of the underlying system. Then scenarios can be generated during the course of the workshop that will promote an appreciation of the real trade-offs that exist among interests or values.

5. Integration

At this point we work to integrate the custom model and the whatIf? technology into the client's planning, consultation and communication processes. At the client's request, this may include establishing ongoing support, maintenance and training services to sustain the model's analytical value and productive life.

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