> My phone screen "fizzbuzz" is having them calculate a standard deviation from an array of data w/out with only basic operators
This is just my n=1 opinion, but this is a terrible test for data science skills. I've had to calculate standard deviation by hand many times in my life, but my short term memory is such that despite doing that dozens of times over the past two decades, I still can't recall the formula off the top of my head. And then there's the whole n vs (n-1) thing in the denominator which has something to do with degrees of freedom, but I would just Google that as soon as I needed to know (depending on exactly what I was trying to do with the data).
So I don't understand how your question in any way tests someone's skills at analyzing data to extract valuable business insights. At best, it tests someone's ability to memorize formulas and minutiae (although I'll grant you that understanding the difference between a sample and the population is important).
Personally, I think take-home interviews with real data sets are the best way to gauge a candidate's skills. You're actually testing them with a work sample, and they are not under artificial time or memorization constraints.
This is just my n=1 opinion, but this is a terrible test for data science skills. I've had to calculate standard deviation by hand many times in my life, but my short term memory is such that despite doing that dozens of times over the past two decades, I still can't recall the formula off the top of my head. And then there's the whole n vs (n-1) thing in the denominator which has something to do with degrees of freedom, but I would just Google that as soon as I needed to know (depending on exactly what I was trying to do with the data).
So I don't understand how your question in any way tests someone's skills at analyzing data to extract valuable business insights. At best, it tests someone's ability to memorize formulas and minutiae (although I'll grant you that understanding the difference between a sample and the population is important).
Personally, I think take-home interviews with real data sets are the best way to gauge a candidate's skills. You're actually testing them with a work sample, and they are not under artificial time or memorization constraints.