  Cohort analysis is a pervasive activity in web analytics. One divides users
into groups according to specific criteria and tracks their behavior over time.
Despite its extensive use, academic circles do not discuss cohort analysis to
evaluate user behavior online. This work introduces an unsupervised
non-parametric approach to group Internet users based on their activities. In
comparison, canonical methods in marketing and engineering-based techniques
underperform. COHORTNEY is the first machine learning-based cohort analysis
algorithm with a robust theoretical explanation.
