Prompting for a confidence level is a very important part of our algorithm.

First, from a practical point of view, the confidence prompt allows the learner to confirm their choice. (If an answer was auto-submitted immediately on selecting an answer, there would be a high number of erroneous submissions - especially when used on mobile.)

It is natural for learners to feel some discomfort having to specify their confidence level. This is actually an important part of having them "place a mental bet" on their answer, which will engage them deeper, and driver better retention.

For questions the learners have high confidence in, they’ll respond automatically – but for questions that they are a bit less confident in, we’ll be able to measure the delay in responding, and examine the learner "certainty" - whether they change their answer before submitting.

All of these, plus other signals that we capture and measure, will be used to assess the learner’s mastery. (We want to understand the likelihood that the learner is guessing, or really knows the answer).