For a learner to increase their mastery strength for a Concept, they must first complete a related Activity proficiently (not just accurately). OttoLearn has a proprietary algorithm that pulls in a number of data points during a learner’s completion of an Activity. This data is used to determine whether the learner is proficient (knew the answer) or not proficient (didn’t know, or was likely guessing).ProTip: In some of our analytics, we reference average proficiency. This is simply the percentage of Activities that were performed proficiently.Some of the factors OttoLearn uses to measure proficiency are:AccuracyConfidenceDurationPast performanceComparison to other learnersOther signalsAccuracy A measure of whether the learner answered an Activity correctly or incorrectly.  ConfidenceEach learner must self-assess their confidence level. This forces the learner to reflect on their choice and sometimes change to another one. We track the learner's self-identified confidence rating, and have a gamified algorithm that rewards learners for properly identifying their confidence level about an answer.Comparative Duration When a learner completes an Activity, we compare their duration for that Activity against the duration of other learners who completed that same Activity at the same mastery strength.Other SignalsOttoLearn uses other signals, and modifies the algorithm from time-to-time, to provide the most accurate representation of whether a learner has completed an Activity proficiently or not.