Introduction to Assumptions

How Assumptions are used to store Model inputs

Overview

In Models, input values are stored separately from Variables and their Calculations.

This allows you to manage the inputs to your Model independently of the calculations within the Model, and to easily create variations on your inputs (through Scenarios and Sensitivities).

This separation means that you can create sets of Assumptions from scratch, without creating the Variables that will reference them, though in practice you will most often generate Assumptions from within a Variable as this is by far the fastest way to do so.

List of Assumptions in Models

The Assumptions Tab

Assumptions List in the Assumptions Tab

Keeping Assumptions separate from Variables means you can thoroughly interrogate and quickly edit all inputs to your Model in one place.

You can do this in the Assumptions Tab, where functionality includes (as per the above screenshot):

• Search and Order your Assumptions with Tag filters, text search, property filters and sorting (1)

• Directly edit Assumption Scenario values (2) - just click in a cell, type, and press Enter to save
• Directly edit Assumption Sensitivity values (3)
• Visualise your assumptions in Charts - just select any Assumptions that relate to each other, and Models will plot them on a chart which you can configure.

Selecting a single Assumption will show you a preview including the details of that Assumptions Unit; Selecting multiple Assumptions will show you a chart (if the selected Assumptions' Units can form a valid series)