The Basics | Notion

In this guide, you'll learn the fundamentals of using Scenarios to transform your data analysis.

1. Locating the Evara Tab in Excel

An “uncertainty” is your educated guess or estimation about a value or range.
- You can think of these as assumption or “conditional” assumptions if they depend on other values.
To specify an uncertainty, select a cell or range in Excel, then click 'Add Uncertainty' in the Evara tab.
Choose an uncertainty type that best matches your intuition about the value. For example, if you think a value is around 5 but could vary, select a range (e.g., 0-10) using the BETWEEN macro.
You’ll notice that cells containing uncertainty macros change every-so-often. In fact, this also includes all other cells that depend those uncertainty cells no matter how deeply nested. This is because an uncertainty macro returns a possible value from your specified assumption. You can also control this by clicking the “Previous/Next” ( ◀️/▶️) in the “Scenarios” tab.

We will talk much more about this on the “What Ifs” page.

After setting up your uncertainties you can reference them like you would any other cell.
You can even chain uncertainties. For instance, using with the running example of planning for the milk desires of the Smiths family:
- You are in charge of buying milk for the Smiths family (of 5)
- Having done this quite a few times you know that the family roughly drinks 5 liters per week. Although you’re not entirely sure you know that you might be off by about 1 liter.
  
  Note the use of “roughly” and “not entirely sure.” We encounter such phrases every day, and each such encounter prompts for the use of an assumption.
- However, even if we actually knew this number you would still expect your family’s desire to vary, maybe even such as 2 liters. Again, this call for another assumption, how much milk is consumed this week given the first assumption of the amount consumed per week.
- To model this we would use the BETWEEN(4,6) macro for the first assumption and the AROUND assumption for the second assumption which depends on the first.
  - As we are in Excel, we can simply reference the call containing the BETWEEN assumption