Also, my guess is that the success rate for interviews would be fairly low, making any comparison of the success rates for different languages/editors even more

Also, my guess is that the success rate for interviews would be fairly low, making any comparison of the success rates for different languages/editors even more statistically shaky. They should definitely publish the total sample size and success percentage for these results to be meaningful. Example: Say they hired 5 out of a 100 applicants who used Python, and 2 out of 20 applicants who used Ruby. That's a 5% success rate vs a 10% success rate, a 100% increase. I'd hardly call that a significant result though. Disclaimer: I'm no statistician either