Does Alphabetical Ordering Affect Investor Behavior? An Empirical Examination of Returns and Trading Volume in BIST 30 Stocks

Öz

The aim of this study is to examine whether alphabetical order bias exists in the stocks included in the Borsa Istanbul 30 Index through return and trading volume indicators. More specifically, the study tests whether presenting stocks to investors in alphabetical order creates a systematic advantage in favor of the stocks positioned at the top of the alphabetical list. For this purpose, the stocks included in the BIST30 index during the 2014/1–2024/3 period were ranked alphabetically by ticker symbol in each period and divided into five equal groups. The G1 group, representing the top of the alphabetical list, was used as the reference category, and whether the other groups differed from G1 in terms of returns and trading volume was analyzed using a period fixed-effects panel regression model. The findings show that there is no statistically significant difference in favor of G1 among the alphabetical groups in the return model. Although some coefficients are statistically significant in the trading volume model, their positive signs are not consistent with the theoretical expectation. The robustness analysis results also support the main findings. Overall, the study shows that being positioned at the top of the alphabetical list does not create a systematic advantage in terms of returns or trading volume for BIST30 stocks.

Anahtar Kelimeler

• Alphabetical Order Bias
• Alphabetical Ordering
• BIST30
• Behavioral Finance
• Trading Volume
• Stock Returns

Alfabetik Sıralama Yatırımcı Davranışını Etkiliyor Mu? BİST30 Hisselerinde Getiri ve İşlem Hacmi Üzerine Ampirik Bir İnceleme.

Öz

Bu çalışmanın amacı, Borsa İstanbul 30 Endeksi’nde yer alan hisse senetlerinde alfabetik sıralama önyargısının var olup olmadığını getiri ve işlem hacmi göstergeleri üzerinden incelemektir. Çalışmanın temel amacı, hisse senetlerinin yatırımcılara alfabetik sırayla sunulmasının, alfabetik listenin üst kısmında yer alan hisseler lehine sistematik bir avantaj yaratıp yaratmadığını test etmektir. Bu amaçla 2014/1–2024/3 döneminde BIST30 endeksinde yer alan hisseler, her dönem hisse kodlarına göre alfabetik olarak sıralanmış ve beş eşit gruba ayrılmıştır. Alfabetik listenin üst kısmında yer alan G1 grubu referans kategori olarak alınmış; diğer grupların getiri ve işlem hacmi bakımından G1’den farklılaşıp farklılaşmadığı dönem sabit etkili panel regresyon modeliyle analiz edilmiştir. Bulgular, getiri modelinde alfabetik gruplar arasında G1 lehine istatistiksel olarak anlamlı bir farklılık bulunmadığını göstermektedir. İşlem hacmi modelinde bazı katsayılar anlamlı olmakla birlikte, katsayıların pozitif olması teorik beklentiyle uyumlu değildir. Sağlamlık analizi sonuçları da ana bulguları desteklemektedir. Genel olarak çalışma, BIST30 hisseleri özelinde alfabetik listenin üst kısmında yer almanın getiri veya işlem hacmi açısından sistematik bir avantaj yaratmadığını göstermektedir.

Anahtar Kelimeler

• Alfabetik Önyargı
• Alfabetik Sıralama
• BIST30
• Davranışsal Finans
• İşlem Hacmi
• Hisse Senedi Getirileri

Kaynakça

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