Storing Model Setup Data

Overview

It was discussed in an earlier section of this documentation that the model hierarchy consists of three levels:

  1. The Project Level
  2. The Domain Model
  3. The Framework Model

In a generalised way, we can state that the Framework Model consists purely of software, while the Domain Model and Project levels are defined purely by data (i.e. setup data). If you are running a desktop version of Cassandra, the framework model software will be installed on your desktop or laptop computer. For the enterprise level, browser-based version, the framework model software will run on our secure cloud server.

Details of the various elements needed to set up your Domain Model and Project is provided in later sections of this documentation. In the following paragraphs, we give a brief overview of the data elements involved for each of these, and how this data is managed in the cloud.

Domain Model Setup Data

The setup components linked to your domain model consist of the following:

  • The JFunction Set that defines your Domain Model.
  • List of Input Data Headers (i.e. column names) and expected data types.
  • Model Parameter definitions.
  • Treatment Type definitions and default unit rates.
  • BCA Candidate Strategy list (only for Benefit-Cost Models).
  • MCDA Treatment Candidates (only for MCDA Models).
  • MCDA Optimisation Setup (parameters and weights for MOORA).
  • Lookup sets with constants, thresholds etc. needed by your Domain Model.
  • Network Functions, which specify which network level statistics to calculate (and optionally assign to parameters), at the end of each modelling period.

Before you can start a Cassandra session, you need to set your Work Bench, as explained in a later section. By setting your Work Bench, you tell Cassandra which of your Domain Models and Projects you want to work on in that session.

Once your Work Bench is set, Cassandra can extract all of the elements listed above from setup data. All of the defined setup data, both for the Domain Model and for Project-level settings, are automatically read before a model run is started.

Project Setup Data

The setup components needed for a specific Project are the following:

  • Budget Constraints (you can give each constraint set a different tag).
  • (Optional) Treatment Rates to override default rates in Domain Model.
  • (Optional) Lookup Tables to override default lookups in Domain Model.