Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, İktisadi ve İdari Bilimler Fakültesi, İşletme Bölümü, Türkiye
Tezin Onay Tarihi: 2009
Öğrenci: ÇAĞDAŞ TAHAOĞLU
Danışman: ZEHRA NURAY GÜNER
Özet:The aim of this master’s thesis is to estimate the return performance of insiders (persons or firms liable for announcing their transactions to the public in accordance with the Capital Markets Board decrees) from their transactions and assess whether outsiders can earn abnormal returns by following reported insider transactions. In the study, Rolling Portfolio Approach has been implemented. As a result of the analysis made, when the purchases and sales of insiders are considered together, it has been observed that they, generally, cannot earn abnormal positive returns from their transactions or that they earn positive abnormal returns in the short periods that follow their transactions. When the returns of the portfolios consisting of stocks of which the insiders are the net purchasers or net sellers are taken into consideration, it has been perceived that the portfolios made up of stocks of which the insiders are net buyers cannot earn daily positive abnormal returns or that they earn daily positive abnormal returns in the short periods following their transactions. In the meantime, net sale portfolios earn statistically significant abnormal negative returns over longer holding periods. On the other hand, it has been perceived that investors replicating insider transactions, in general, cannot earn abnormal returns by employing an investment strategy founded on following the purchases and sales of insiders together. Moreover, it has been observed that an investment strategy based on buying the stocks of which the insiders are the net purchasers does not bring abnormal positive returns or that it can bring abnormal positive returns in the brief periods after the transactions. In contrast, it has been observed that, generally, in the sample period analyzed in the study, by avoiding buying or selling stocks of which the insiders are the net sellers, outsiders can evade daily negative abnormal returns. Findings of this thesis have important implications for the efficiency of the Istanbul Stock Exchange. Results indicate that the Istanbul Stock Exchange is not Semi Strong or Strong Form Efficient.