However, the following types of top students are significantly less likely to practice on interviewing.io, for example:
- Seniors who have already done internships at top companies (Google, FB, Stripe, etc)
- People who excelled at programming contests and generally enjoy algorithmic challenges: IOI, TopCoder, Project Euler, etc.
- People who have built awesome open-source projects that got significant recognition. For example, Feross Aboukhadijeh was a Stanford student who built Youtube Instant and immediately received an internship offer from Youtube founder Chad Hurley [1]. I doubt people like him would need to practice on interviewing.io
- In general, students who are regarded as top n% of MIT/Stanford/CMU CS are inundated with recruiting pitches (I speak from experience as a CS graduate from one of these universities. Most of us constantly received an overwhelming number of e-mails from recruiters, many of them offering to get us to get fast-tracked in the interview process).
Granted, not every top CS student at MIT/Stanford/CMU has done competitive programming or built really cool stuff that's widely recognized. But a significant percentage of the top n% of students do have this kind of background (admittedly, this is somewhat of a circular definition of "top" student). That's what I mean by selection bias.