0
votes
1answer
216 views

Intersection of plane with quadratic regression surface

A quadratic OLS regression with two predictors is defined as: $Z = b_0 + b_1X + b_2Y + b_3X^2 + b_4XY + b_5Y^2 + e$ (1) If this regression surface is plotted, it can look like this ($b_0=10, ...
2
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1answer
104 views

Is the intersection of the diagonal with a graph always transverse in characteristic zero

Let X be a projective smooth connected curve over $\mathbf{C}$. Let $f:X\to X$ be a non-constant morphism. Is the intersection of the diagonal $\Delta_X$ and the graph $\Gamma_f$ on $X\times X$ ...