Yatırımcı Psikolojisi Bağlamında Risk ve Belirsizlik Göstergelerinin Borsa İstanbul Üzerindeki Etkileri

Öz

Bu çalışma risk ve belirsizlik göstergelerinin yatırımcı psikolojisini yansıtan piyasa davranışları aracılığıyla Borsa İstanbul (BIST 100) üzerindeki etkilerini bütüncül bir perspektiften incelemektedir. Şubat 2018–Aralık 2024 dönemi için Kesirli frekanslı bootstrap Fourier ARDL metodolojisi ile yürütülen analizde, yalnızca piyasa riskini değil, yatırımcıların korku ve iyimserlik algısını da yansıtan göstergeler kullanılmıştır. Bulgular, ülke riskindeki ve küresel piyasa korkusundaki artışın hisse senedi getirilerini olumsuz etkilediğini; döviz kuru oynaklığı ve ekonomik politika belirsizliğinin bu negatif etkiyi güçlendirdiğini göstermektedir. Buna karşın, kripto para piyasalarındaki iyimserliğin piyasalara pozitif yönde yansıdığı saptanmıştır. Sonuçlar, Türk hisse senedi piyasasında yatırımcı davranışının risk ve belirsizlik dinamiklerine duyarlılığını ortaya koymakta; yatırımcı güveni ve finansal istikrar için risk primini düşürücü, kur istikrarını koruyucu ve öngörülebilir ekonomi politikalarının önemini vurgulamaktadır. Ayrıca, kripto para piyasasına ilişkin eğilimlerin hisse senedi piyasasına yayılım etkisi, hem politika yapıcılar hem de yatırımcılar tarafından karar süreçlerinde dikkate alınabilecek bir referans aracı olarak değerlendirilebilir.

Anahtar Kelimeler

• Yatırımcı Psikolojisi;
• Piyasa ve Politika Belirsizliği
• Risk Algısı
• Fourier ARDL Modeli

The Impact of Risk and Uncertainty Indicators on Borsa Istanbul through the Lens of Investor Psychology

Abstract

This study examines the impact of risk and uncertainty indicators on the Borsa Istanbul (BIST 100) through the lens of investor psychology and the resulting market behavior, taking a holistic perspective. Utilizing the Fractional Frequency Bootstrap Fourier ARDL methodology for the period February 2018-December 2024 the analysis employs indicators that reflect not only market risk but also investors' perception of fear and optimism. The findings reveal that increases in country risk and global market fear (VIX) negatively affect stock returns, while exchange rate volatility and economic policy uncertainty amplify this negative impact. Conversely, optimism in cryptocurrency markets is found to have a positive spillover effect on the equity market. The results underscore the high sensitivity of investor behavior in the Turkish stock market to risk and uncertainty dynamics. They emphasize the critical importance of implementing policies that reduce the risk premium, ensure currency stability, and promote predictable economic policies to safeguard investor confidence and financial stability. Furthermore, the spillover effect from cryptocurrency market sentiment can be viewed as a valuable reference tool for both policymakers and investors in their decision-making processes.

Keywords

• Investor Psychology
• Market and Policy Uncertainty
• Risk Perception
• Fourier ARDL Model

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