> The point is whether asking math questions at all is valuable compared to the other questions you asked. The author uses a graph search problem as an example

> The point is whether asking math questions at all is valuable compared to the other questions you asked. The author uses a graph search problem as an example - which is a very typical problem in IT. How do you approach such a problem? This is a valid math question that certainly adds value compared to other questions I might ask. It actually checks for multiple things: Does the candidate have a grasp of the underlying mathematical concepts. How does the candidate approach a problem decoupled of the actual real-world constraints of a programing language? Can the candidate describe a problem in clear, concise terms? Same for set theory: intersection, union, functions mapping input to output. Complexity analysis of algorithms - all of that is valuable knowledge and it's absolutely valid to ask people for that. How does binary AND/OR/XOR work? How does an exponential decay curve look like compared to a gauss or linear curve? This GH issue https://github.com/elasticsearch/elasticsearch/issues/3423 https://github.com/elasticsearch/elasticsearch/issues/3423 was posted on HN as example of a great feature description and it's full of formulas describing how it works. Vectors, matrix multiplication is a fundamental thing when you're doing natural language processing. Statistical problems are not exactly uncommon in programming either. Map/reduce are mathematical concept. What's wrong asking for that? Failing the answer does not mean that the interview is over, but to assert a candidate I need to know what she knows. As annoying as it sometimes is, math is _the_ _fundamental_ underpinning of what we do every day. > As far as that goes, I try to question them about school projects. Totally fine and I agree. Still - what's wrong with asking math questions? > Google has admitted that all of their algorithm type questions are not good predictors of on the job performance You're running into a problem if you hire only for math knowledge. But -repeat- that's not what I've been advocating.