Step 5. Review Certainty Matrix

2. How to review and revise Certainty Matrices

This is your team's opportunity to change any assumption ratings... to ensure assumptions are properly investigated.

Within Minesweeper software, click the left-hand step, “5: Review Certainty Matrix.” Then as a team, carefully click through each of the 6 Certainty Matrix tabs to review them.

As shown below, you’ll look at the matrix and ask this question: “Have we properly placed this assumption in terms of certainty and impact?” The following can help:

  • If anyone on the team is in doubt, click the assumption tab on the left and read the Sources of Truth and Findings… to remember why the assumption was rated as you now see it.
  • To make a change in either the impact or certainty rating, click this same assumption tab and make your changes on the ratings page.
  • If you do make changes to the ratings, be sure to make notes in the Sources of Truth and Findings fields… to help you remember your rationale later.
  • When in doubt, put an assumption in a yellow “Caution” or red “Danger” zone, not the green “Safe” zone. Once they are labeled “Safe” it’s unlikely your team will investigate further.


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