Proceedings

CONCLUSIONS
We can conclude by showing that, in today’s extremely dynamic and unpredictable
business environment, the decision takers invest in various categories of assets in
order to maintain a competitive advantage. Certain securities and projects may be
integrated a mixed assets portfolio. Thus, the mixed assets portfolio amplifies the
investors’ opportunities. Regarding the expected efficiency and risk, the two objective
functions have been implemented as a bi-objective programming model than can
reflect the investor’s hopes and expectation once the mixed assets portfolio has been
determined, by means of a selection problem with transactional costs.
Moreover, the investors’ vaguely expressed expectations regarding the efficiency and
risk levels are considered to be fuzzy numbers in order to be formally illustrated in a
way that allows them to determine the optimal portfolio structure, by means of
specialized algorithms. The experimental results show that the suggested model can
successfully generate a portfolio strategy, depending on the degree of satisfaction
expected by the investor.
ACKNOWLEDGEMENT
This work was supported by CNCSIS –UEFISCSU, project number PNII – IDEI
_1805/2008.
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