These questions would get you: recent grads, who have not forgotten all the math; hackernews crowd, who reviewed pg research from years back; developers, who ha

These questions would get you: recent grads, who have not forgotten all the math; hackernews crowd, who reviewed pg research from years back; developers, who have taken some popular AI/ML class. And while this is all good, this is certainly not enough. In reality applied data science is not different from any other area. You get proficiency with experience, as usual.