Quantitative Methods

Questionnaire design

System Usability Scale

Net Promoter Score

A/B testing

Multivariate testing

Task success rate

Task completion time

Error rate and help-seeking

Eye-tracking experiments

Physiological measurement

Log and instrumentation analysis

Funnel and retention analysis

Significance and practical importance

Novelty and learning effects

Questionnaires and rating scales

Single-item and short scales

Recommendation-style metrics and their controversies

Experimental design and controls

Statistical significance and effect size

Multiple comparisons and result picking