# Notation for the variance in papers

Here is a screenshot from : LIM Quadratic hedging and mean variance portfolio selection with random parameters in an incomplete market

When I deal with mean variance portfolios, I usually see the notation J as something to be minimized. I think it denotes the variance, but why one would use the letter J ? Is it something simply conventioned or does it have a story ?

• The use of the variable J for the thing to be minimized (or maximized) is very common in Mathematics, for example in the Calculus of Variations en.wikipedia.org/wiki/Calculus_of_variations , Stochastic Control etc. It is not just in Finance or for the variance and is probably very old (maybe even goes back to people like Lagrange etc. ??? I don't know who started it). – Alex C Nov 16 '19 at 16:52