Portföy optimizasyonunda alt kısmi moment ve yarı-varyans ölçütlerinin kullanılması

Portföy optimizasyonu, esas olarak getirinin maksimize edilmesi ve riskin minimize edilmesinin hedeflendiği çok amaçlı bir optimizasyon problemidir. Problemin çözümü sonucunda elde edilecek sonuçların geçerliliği açısından, bu problemin parametrelerinin doğru olarak tanımlanması önem taşımaktadır.Çeşitli araştırmacılar tarafından yatırımcıların risk algısını daha iyi temsil ettikleri belirtilen kayıp riski ölçütlerinin arasında bulunan yarı-varyans ve alt kısmi moment ölçütleri kullanılarak portföy optimizasyonu uygulamasının gerçekleştirildiği bu çalışmada, pareto etkin portföylerin elde edilmesi için sezgisel hesaplama tekniklerinden birisi olan genetik algoritmaların kullanılması tercih edilmiştir. Geliştirilen uygulama, İstanbul Menkul Kıymetler Borsası (İMKB) 100 endeksine kayıtlı hisse senetlerinin geçmiş verileriyle test edilmiş ve elde edilen etkin sınırların elde edilmesi beklenen sonuçlarla uyum içerisinde bulunduğu gözlenmiştir.

Uses of variance and lower partial moment measures for portfolio optimization

Portfolio optimization is mainly a multi-objective optimization problem that aims to maximize expected return while minimizing risk. It is important to define the meaning of these parameters accurately, in terms of validity that is acquired by the solution of the problem. In this study, portfolio optimization is implemented through two downside risk measures, semi-variance and lower partial moment, which are stated by researchers to be better representation for investors risk perception. Genetic algorithms, which are among the heuristic computational methods, are used to achieve pareto-efficient portfolios. The implementation is tested by historical data of the shares that are authorized to Istanbul Stock Exchange (ISE) 100 Index, and it is observed that the efficient portfolios achieved by the implementation are consistent with expected results.

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