W2 - Quizz Q2 mistake?


I came across multiple occurrences of questions being quite “debatable” in the quizzes of DLS3, so I would like some clarification before submitting my test. In this image, the two possibilities rise question to me:

  • In the first line, are we to assume that the product of 2 vectors is the dot product, as in uv=np.dot(u.T, v)?
  • In the second image, are we to suppose that parentheses around the second term y_j^i have been forgotten? Or were they purposefully omitted? There also lacks a parentheses at the end of the first line so it’s kind of impossible to know what we’re expected to answer here…

I really find the quizzes of DLS3 hard to get 100% because of multiple open interpretation of questions and answers…

Thanks for your help!

I don’t think we have enough context to answer your first question. Who said anything about dot products? That is a mathematical expression that is shown there. You could compute that with two dot products: one for the y = 1 term and one for the y = 0 term of that formula. That’s not all it would take, but that would be the “core” of the computation. Of course it requires that you know the orientation of the vectors involved in order to know which one of them (if any) must be transposed.

For the second question, I think you can assume they just accidentally missed the parens on the superscript.