Problems Found per Tester: Discovery Rate p, 1 − (1 − p)^n, Testers Needed and a Discovery Curve
This lesson is part of the course
In this lesson
You estimate from six sessions how likely one tester is to hit a problem, draw the share of problems that n testers find, work out how many testers reach a 90 % target and chart the discovery curve.
Buy the course once for $9.99 to unlock every lesson and lab, the final exam and the certificate – lifetime access, no subscription.
Lessons in this course
- Task Success: Completion Rates, an Adjusted 95 % Range with z = 1.96 and a Pass Verdict Locked
- Time on Task: Completed Attempts Only, Median vs Geometric Mean with LN & EXP, Slow Outliers Locked
- Errors & Efficiency: Errors per Tester, Shortest Path vs Clicks and a Lostness Score Locked
- Questionnaire Scores: Positive & Negative Items, Item Contributions and a 0–100 Score per Tester Locked
- Problems Found per Tester: Discovery Rate p, 1 − (1 − p)^n, Testers Needed and a Discovery Curve Locked
- Issue Prioritisation: Severity × Frequency × Task Importance, a Ranked List and Effort vs Impact Locked
- Card Sorting & Tree Tests: Co-occurrence Matrix, Agreement %, Tree-Test Success and Directness Locked
- Capstone – Target Sizes & Choices: Movement Time a + b·LOG(D/W + 1, 2), Choice Time and a Before/After Chart Locked