Defined-contribution plans represent a major organizational form for investors´ retirement savings. Today more than one third of all workers are enrolled in 401K plans.(...)

Elton, E.J., Gruber, M.J. and Padberg, M.W. Simple criteria for optimal portfolio selection.--Rudd, A. and Rosenberg, B. Realistic portfolio optimization.--Bawa, V.S. and Chakrin, L.M. Optimal portfolio choice and equilibrium in a lognormal securities market.--Levy, H. Does diversification...