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Tagged with economics convex-optimization
3 questions
4
votes
2
answers
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Can the sum of quasiconcave functions always be made quasiconcave?
Let $f_1,f_2$ be two smooth quasiconcave functions defined on a convex subset of $\mathbb{R}^d$.
It is known that $f_1+f_2$ is not necessarily quasiconcave.
Does there always exist monotonically ...
4
votes
3
answers
2k
views
Zero lambda, zero constraint in the complementary slackness condition of the Kuhn-Tucker problem
Complementary slackness condition in the KKT theorem states that:
$\lambda_i^*\geq0; \lambda_i^*h_i(x^*)=0 $
The usual reasoning goes like this: either constraint is clack $h_i(x^*)>0$ and then ...
3
votes
1
answer
886
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Is the max of two supermodular functions supermodular?
A function $f: \mathbb{R} \times \mathbb{R} \to \mathbb{R}$ is supermodular if for every $x'>x$ and $y'>y$,
$$f(x',y') + f(x,y) > f(x',y) + f(x,y').$$
Suppose $f$ and $g$ are supermodular, ...