İSTANBUL MENKUL KIYMETLER BORSASINDA PİYASA SÜRPRİZLERİNE YATIRIMCI TEPKİSİ

Öz

Bu çalışma İstanbul Menkul Kıymetler Borsasına sürpriz bir bilgi gelişi karşısında yatırımcının tepkisini incelemektedir. IMKB100 endeksi için sonuçlar sürpriz bilgi gelişi karşısında yatırımcının davranışının Aşırı Tepki Hipotezi’ne uygun olduğunu göstermektedir. Bu durum özellikle negatif etkisi olan bilgi gelişi sonrası daha belirgindir. Daha likit ve pazar etkinliği fazla olan şirketler grubunu kapsayan IMKB30 endeksi aynı yapıyı göstermemektedir Çalışmanın bir sonucu; endeksteki aşırı düşmeler sonrası IMKB100 endeksine yatırım yapmanın anormal getiri sağlayabileceğidir. Sonuçlar Sermaye Piyasası Kurulu’nun likiditesi ve toplam piyasa değeri düşük olan hisselerin alım satımı için daha fazla bilgi verilmesini zorunlu kılan son değişikliklerini destekler niteliktedir

Anahtar Kelimeler

• İstanbul Menkul Kıymetler Borsası, Pazar Etkinliği, Aşırı Tepki, Belirsizlik Hipotezi, Belirsizlik, Anormal Getiri

INVESTOR REACTION TO MARKET SURPRISES ON THE ISTANBUL STOCK EXCHANGE

Öz

This paper examines the reaction of investors to the arrival of unexpected information on the Istanbul Stock Exchange. The empirical results suggest that the investor reaction following unexpected news on the ISE100 is consistent with Overreaction Hypothesis especially after unfavorable market surprises. Interestingly such pattern does not exist for ISE30 index which includes more liquid and informationally efficient securities. A possible implication of this study for investors is that employing a semi contrarian investment strategy of buying losers in ISE100 may generate superior returns. Moreover, results are supportive of the last regulation change of Capital Market Board of Turkey which mandates more disclosure regarding the trading of less liquid stocks with lower market capitalization.

Anahtar Kelimeler

• Istanbul Stock Exchange, Market Efficiency, Overreaction, Uncertain Information Hypothesis, Uncertainty, Abnormal Returns

Kaynakça

1. ABARBANELL, J.S.; BERNARD, V.L. (1992). Tests of Analysts' Overreaction/ Underreaction to Earnings Information as an Explanation for Anomalous Stock Price Behavior. Journal of Finance, Vol. 47 (3), pp 1181-1207
2. AJAYI, R., MEHDIAN, S. (1994). Rational investors reaction to uncertainty: evidence from the World’s major markets. Journal of Business Finance and Accounting 21, pp 533-545.
3. BARBER B.M., ODEAN T. (2008). All that glitters: the effect of attention and news on the buying behavior of individual and institutional investors. Review of Financial Studies, 21 (2): pp.785-818.
4. BLACK F. (1986), Noise, Journal of Finance 41 (3): pp.529-543.
5. BROWN K.D., HARLOW W.V., TINIC S.M. (1988), Risk aversion, uncertain information, and market efficiency. Journal of Financial Economics 22, pp.355-385.
6. DE BONDT, W.F., THALER R.H. (1985). Does the stock market overreact? Journal of Finance 40, pp.793-805.
7. DE BONDT, W.F., THALER R.H. (1987). Further evidence on investor overreaction and stock market seasonality. Journal of Finance 42, pp.557-581.
8. DELONG, J.B., SHLEIFER, A., SUMMERS, L.H., WALDMAN, R.J. (1990), Unexpected favorable feedback investment strategies and destabilizing rational speculation, Journal of Finance 45, pp.379-95.

9. FAMA, E. (1970), Efficient capital markets: a review of theory and empirical work. Journal of Finance, 25, pp.383-417.
10. FANG, L., PERESS, J. (2009) Media coverage and cross-section of stock returns. Journal of Finance, 64 (5), pp.2023-2052.
11. HONG, H., STEIN J.C. (1999). A unified theory of underreaction, momentum trading, and overreaction in asset markets. Journal of Finance, 54, pp.2143-2184.
12. HONG, H., LIM, T., STEIN, J.C. (2000). Bad news travels slowly: size, analyst coverage, and the profitability of momentum strategies. Journal of Finance, 55 (1), pp.265–295.
13. JEGADEESH, N. TITMAN, S. (1993). Returns to Buying Winners and Selling Losers: Implications for Stock Market Efficiency. Journal of Finance, 48 (1), pp. 65-91
14. KAHNEMAN, D., TVERSKY, A. (1979). Prospect theory: an analysis of decision under risk, Econometrica. 47(2), pp.263-292.
15. KAHNEMAN, D., RIEPE M.W. (1998). Aspects of investor psychology. The Journal of Portfolio Management 24 (4), pp.52-65.
16. KAMARA, A. (1997). New evidence on the Monday seasonal in stock returns. Journal of Business, 70, pp.63-84.
17. KYLE, A.S. (1985). Continuous auction and insider trading. Econometrica, 53 (6), pp.1315- 1335.
18. LARSON, S.J., MADURA, J. (2001). Overreaction and under reaction in the foreign exchange market. Global Finance Journal. 12 (2), pp.153-177.
19. LEE, C.M., SHLEIFER, A., THALER, R.H. (1990). Anomalies: closed-end mutual funds. Journal of Economic Perspectives. 4, pp.153-164.
20. LEE, C.M., SHLEIFER, A., THALER, R.H. (1991). Investor sentiment and the closed-end fund puzzle. Journal of Finance, 46, pp.75-110.
21. MACKINLAY, A.C. (1997). Event studies in economics and finance. Journal of Economic Literature. 35 (1), pp.13-39.
22. NG, L., FEI, W. (2006). Revealed stock preferences of individual investors: evidence from Chinese equity markets. Pacific Basin Finance Journal, 14 (2), pp.175-192.
23. POTESHMAN A.M. (2001). Underreaction, overreaction, and increasing misreaction to information in the options market. Journal of Finance, 56 (3), pp.851-876.
24. RUBACK, R.S. (1982). The effect of discretionary price control decisions on equity values. Journal of Financial Economics, 10, pp.83-105.
25. SHLEIFER, A. (2000). Inefficient markets: an introduction to behavioral finance, London: Oxford University Press.
26. TETLOCK P.C. (2010). Does public financial news resolve asymmetric information? Review of Financial Studies. 23 (9), pp.3520-3557.
27. ZHANG, X. F. (2006) Information Uncertainty and Stock Returns. Journal of Finance, 61 (1), pp. 105-136.