How are the Certainty and Margin of Error calculated?

When you hover over a datapoint in the dashboard, you'll see the following pop-up, which includes information on the Certainty and Margin of Error for that datapoint.

Certainty

The traffic light system (High = green, Medium = yellow, Low = red) is intended to help you understand the quality of the datapoint at a glance, based on the Margins of Error.

The thresholds are defined as follows:

High: Margin of Error is less than or equal to 3%

Medium: Margin of Error is greater than 3% and less than or equal to 10%

Low: Margin of Error is greater than 10%