Sándor Zoltán Németh

4 Questions 11 Answers 0 Followers

Questions related from Sándor Zoltán Németh

Let A be a square matrix. If the mapping Ax^+ is Minty-Browder monotone, then A is positive semidefinite. Is the converse true?

x=(x_1,...,x_n)^T, x^+=(max(x_1,0),...,max(x_n,0)), A has n lines and Ax^+ means A multiplied by x^+. Everything is real.

07 July 2016 5,340 1 View

Which results are more important in mathematics, the ones with an immediate impact (few years) or the ones with a delayed impact (several decades)?

Should we always try to achieve immediate impact for our results? How to decide if a result is promising (that is, it will be important several decades later) or not? Can a mathematical result...

09 September 2015 2,669 4 View

Does anybody know about "true" applications of cone-complementarity problems where the cone is essentially different from the nonnegative orthant?

I consider an application a "true" one if it does not come as a reformulation of an optimization problem. I already know about applications of the second order and positive semidefinite...

06 June 2015 3,427 4 View

I think isotonic regression should be important in finance. Does anybody know about any applications of isotonic regression in finance?

My feeling is based on the following idea: Expected behaviour of financial data could have ordering properties. For example one may expect the increase in price of some stock in a given time...

06 June 2015 3,578 4 View