Notations
= instruments in the portfolio;
= index of instrument in the portfolio;
= number of scenarios;
= index of scenarios;
= vector of weights of instruments in the portfolio, ;
= rate of return of instrument i under scenario ;
= random return vector;
= loss function;
= average rate of return of the i-th instrument over set of scenarios ;
= target level of rate of return of the portfolio;
= bound on the portfolio CVaR;
= penalty coefficient;
= confidence level in CVaR.
minimizing portfolio CVaR
(CS.1) |
subject to
budget constraint
(CS.2) |
constraint on the portfolio mean return
(CS.3) |
no short constraints
(CS.4) |
The constraint (CS.3) may be infeasible. To prevent possible infeasibility we have added to the performance function a compensation variable assuring feasibility.
minimizing weighted average of risk and penalty
(CS.5) |
subject to
budget constraint
(CS.6) |
constraint on portfolio mean return combined with penalty variable
(CS.7) |
no short constraints and non-negativity constraint on penalty variable
(CS.8) |
maximizing portfolio mean return
(CS.9) |
subject to
CVaR constraint
(CS.10) |
budget constraint
(CS.11) |
no short constraints
(CS.12) |