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Comment by apwheele

My experience like this was for a data scientist position at Facebook in 2022.

So the question was something like, here is a table of predicted probabilities for credit card transactions (hypothetical table, I do not remember the exact quantities), but it looked something like this:

    Amount, Probability, ActualFraud
       $5 ,    0.2     ,  0
     $100 ,    0.5     ,  0
       $3 ,    0.7     ,  1
       $1 ,    0.9     ,  1
And then the question was "what was the threshold used to maximize (precision|recall)?" (I cannot remember which metric they were asking for).

My response was that a proper decision model should take the dollar amount of the transaction into consideration, so the decision should more like be `$*p > threshold`, where this threshold meets your precision and recall for preventing dollars lost instead of the binary yes/no.

The interviewers English was not great, so after all that I was just like "well to answer your exact question, it could be anywhere between `0.5 < p <= 0.7`"

Did not make the second round!

parent apwheele 3 months ago

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