Yazar "Polat, Ali Yavuz" seçeneğine göre listele
Listeleniyor 1 - 11 / 11
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Agency theory: a review in finance(2020) Tekın, Hasan; Polat, Ali YavuzThe problems of agency and risk sharing arise due to the separation of ownership and control of a large firm, when conflicts of interest exist between principals (owners) and agents (managers). The main source of these problems is asymmetric information, which implies an agency cost for the principal. Agency theory, which is still one of the fundamental theories in corporate finance, focuses on minimizing costs in agency relations. This study critically evaluates the principal-agent relations, focusing on the interaction between the shareholder-manager and bondholder-shareholder in corporate finance.Öğe The Ascent of Geopolitics: Scientometric Analysis and Ramifications of Geopolitical Risk(Taylor & Francis Ltd, 2023) Aysan, Ahmet Faruk; Polat, Ali Yavuz; Tekin, Hasan; Tunali, Ahmet SemihIn recent years, geopolitical risk (GPR) has been a crucial factor in investment decisions and stock markets. Therefore, we explore the research on the GPR by employing bibliometric and scientometric analytical techniques. We find 366 scientific contributions in December 2021 from the Scopus database by searching 'Geopolitical risk' in abstracts, keywords, and titles. Our findings show that GPR research has gained momentum in the last three years. Specifically, the journal Defence and Peace Economics has one of the highest numbers of research and citation on GPR. Authors in Asia also dominate the GPR literature. Overall, this study contributes to the literature by presenting the existing research that may give new insights for prospective studies in GPR.Öğe Assessing the impact of Covid-19 pandemic in Turkey with a novel economic uncertainty index(Emerald Group Publishing Ltd, 2022) Mugaloglu, Erhan; Polat, Ali Yavuz; Tekin, Hasan; Kilic, EdanurPurpose This study aims to measure economic uncertainty in Turkey by a novel economic uncertainty index (EUI) employing principal component analysis (PCA). We assess the impact of Covid-19 pandemic in Turkey with our constructed uncertainty index. Design/methodology/approach In order to obtain the EUI, this study employs a dimension reduction method of PCA using 14 macroeconomic indicators that spans from January 2011 to July 2020. The first principal component is picked as a proxy for the economic uncertainty in Turkey which explains 52% of total variation in entire sample. In the second part of our analysis, with our constructed EUI we conduct a structural vector autoregressions (SVAR) analysis simulating the Covid-19-induced uncertainty shock to the real economy. Findings Our EUI sensitively detects important economic/political events in Turkey as well as Covid-19-induced uncertainty rising to extremely high levels during the outbreak. Our SVAR results imply a significant decline in economic activity and in the sub-indices as well. Namely, industrial production drops immediately by 8.2% and cumulative loss over 8 months will be 15% on average. The losses in the capital and intermediate goods are estimated to be 18 and 25% respectively. Forecast error variance decomposition results imply that uncertainty shocks preserve its explanatory power in the long run, and intermediate goods production is more vulnerable to uncertainty shocks than overall industrial production and capital goods production. Practical implications The results indicate that monetary and fiscal policy should aim to decrease uncertainty during Covid-19. Moreover, since investment expenditures are affected severely during the outbreak, policymakers should impose investment subsidies. Originality/value This is the first study constructing a novel EUI which sensitively captures the critical economic/political events in Turkey. Moreover, we assess the impact of Covid-19-driven uncertainty on Turkish Economy with a SVAR model.Öğe Bitcoin-specific fear sentiment matters in the COVID-19 outbreak(Emerald Group Publishing Ltd, 2022) Polat, Ali Yavuz; Aysan, Ahmet Faruk; Tekin, Hasan; Tunali, Ahmet SemihPurpose This study aims to investigate the effect of fear sentiment with a novel data set on Bitcoin's (BTC) return, volatility and transaction volume. The authors divide the sample into two subperiods to capture the changing dynamics during the COVID-19 pandemic. Design/methodology/approach The authors retrieve the novel fear sentiment data from Thomson Reuters MarketPsych Indices (TRMI). The authors denote the subperiods as pre- and post-COVID-19 considering January 13, 2020, when the first COVID-19 confirmed case was reported outside China. The authors use bivariate vector autoregressive models given below with lag-length k, to investigate the dynamics between BTC variables and fear sentiment. Findings BTC market measures have dissimilar dynamics before and after the Coronavirus outbreak. The results reveal that due to the excessive uncertainty led by the outbreak, an increase in fear sentiment negatively affects the BTC returns more persistently and significantly. For the post-COVID-19 period, an increase in fear also results in more fluctuations in transaction volume while its initial and cumulative effects are both negative. Due to extreme uncertainty caused by the COVID-19 pandemic, investors may trade more aggressively in the initial phases of the shock. Practical implications The authors are convinced that the results in this paper have more far-reaching implications for other markets regulated by the states. BTC provides a natural benchmark to understand how fear sentiment drives and impacts the markets isolated from any interventions. Hence, the results show that in the absence of regulatory frameworks, market dynamics are likely to be more volatile and the fear sentiment has more persistent impacts. The authors also highlight the importance of using micro, asset-specific sentiment measures to capture market dynamics better. Originality/value BTC is not associated with any regulatory authority and is not produced by the governments and central banks. COVID-19 as a natural experiment provides an opportunity to explore the pure effects of market sentiment on BTC considering its decentralized and unregulated features. The paper has two main contributions. First, the authors use BTC-specific fear sentiment novel data set of TRMI instead of more general market sentiments used in the existing studies. Next, this is the first study to examine the association between fear and BTC before and after COVID-19.Öğe Do market differences matter on dividend policy?(Elsevier, 2021) Tekin, Hasan; Polat, Ali YavuzWe investigate the dividend policies of firms in the United Kingdom to understand whether firms in different markets use dividends as a signaling or disciplining device. The sample consists of 1247 firms from the highly regulated Main Market (MAIN) and relatively unregulated Alternative Investment Market (AIM) for the period 2002-2017. We find that firms in AIM pay lower dividends than their MAIN counterparts. However, during turbulence, AIM firms decrease dividends lower than MAIN firms. In line with the signaling hypothesis, AIM firms with increased profitability are more likely to increase dividends. These results suggest that AIM firms depend more on the signaling feature of the dividends, whereas MAIN firms use dividends as a disciplining device to limit managerial discretion. Specifically, we find that AIM firms facing bigger agency problems pay lower dividends compared to other AIM firms, in line with the outcome view of agency theory. Copyright (C) 2020, Borsa Istanbul Anonim Sirketi. Production and hosting by Elsevier B.V.Öğe The global financial crisis and capital structuredecisions of turkish smes: a review(2020) Tekın, Hasan; Polat, Ali YavuzDue to the arising uncertainties with the global financial crisis, capital structure decisions became crucial for Turkish firms, especially small and medium-sized (SMEs) firms. Since SMEs face higher information asymmetry, transaction costs and risk, they face more difficulties in accessing finance during the financial market turmoil. In this review, we comparatively analyze findings from capital structure decisions for Turkish firms. As might be anticipated, we expect that SMEs should take more precautionary steps under the severe crisis conditions compared to listed firms in Borsa Istanbul.Öğe Is leverage a substitute or outcome for governance? Evidence from financial crises(Emerald Group Publishing Ltd, 2023) Tekin, Hasan; Polat, Ali YavuzPurpose The authors investigate the impact of governance on the leverage of East Asian firms in the financial crisis context, in order to understand the puzzle whether debt acts as a substitute for governance or an outcome of the governance mechanism. Design/methodology/approach The authors use 86,030 firm-years and the country-level governance data from eight East Asian countries over the period 1996-2017. The authors employ the fixed effects (FE) model, in the main analysis and the weighted least squares model, as a robustness check in order to compare the two competing hypotheses of agency theory, substitute and outcome models. Findings The authors' results show that debt acts as a substitute for governance before the GFC, but during and after the GFC the picture changes. Namely, debt acts as an outcome of the governance mechanism during the GFC and its aftermath. Since during financial downturns both agency costs increase, and information asymmetry widens, firms in poor-governed countries may be reluctant to increase their leverage in order not to face financial distress and additional restrictions. Thus, the results imply that the use of debt as a tool to mitigate agency conflicts and a substitute for governance strongly depends on the environment that the firms operate and the general macroeconomic conditions, such as facing a financial crisis or not. Research limitations/implications This study provides an interesting case of the firms' capacity to raise money during a crisis and that governance plays an important role in borrowing activities of firms. This will undoubtedly help motivating owners and policymakers for improving governance. The authors' findings may be useful for policymakers to develop policies considering the adverse effects caused by exogenous shocks. This is crucial because the severity of GFC as a shock seems to change the macro and institutional environment that firms operate. While the authors properly address the research hypotheses using country governance data, future research may employ corporate governance data to attain firm-level results by testing two competing hypotheses. Originality/value There are several important areas where this study makes original contributions. First, while Tsoy and Heshmati (2019) focus on the dynamics of capital structure for only Korean firms, the authors extend the sample including eight East Asian countries considering the impact of country governance on capital structure policy. Specifically, this study is the first in using the robust country governance data, which differs by country and year, in the crisis context. Next, the authors investigate both the AFC and GFC to compare whether these two crises have different effects on capital structure policy of East Asian firms. Finally, the authors aim to understand whether leverage is used as a substitute for governance or an outcome of governance mechanism considering recessions.Öğe Is saving vital? Evidence from the financial crisis(Univ Oviedo, 2020) Tekin, Hasan; Polat, Ali YavuzWe use a sample of 8,561 firm-years from the highly regulated Main Market (MAIN) and relatively unregulated Alternative Investment Market (AIM) in the United Kingdom to analyse the impact of financial restrictions on optimal cash holdings in the context of financial crises. Employing system generalised methods of moments, we find that AIM firms have a faster adjustment speed of cash as confirmed by precautionary and transaction motives over 2002-2017. However, AIM firms decrease (increase) their adjustment speed of cash more than MAIN firms during (after) the financial crises.Öğe Küresel finansal kriz ve nakit tutma ayarlama hızı(2021) Tekın, Hasan; Polat, Ali Yavuz; Mugaloglu, ErhanDış finansmana erişimin sınırlı olduğu zamanlarda nakit tutma stratejik bir öneme sahip olmaktadır. Likit varlıklar, özellikle dış şoklarla birlikte firmaların varlıklarını devam ettirebilmeleri için çok önemli hale gelmektedir. Öyle ki, nakit varlıkların talep fonksiyonu, doğal bir deney imkânı sunan 2008-2009 Küresel Finansal Krizine (KFK) bağlı olarak değişebilmektedir. Optimum nakit tutma teorisine dayanan bu çalışma, KFK’den önce ve sonra Borsa İstanbul (BİST)'da işlem gören finansal olmayan firmaların nakit varlıklarının ayarlama hızını 2003-2018 zaman dilimi için incelemektedir. Herhangi bir içsellik problemini azaltmak için genelleştirilmiş momentler yöntemi (GMM) kullanılmıştır. Bulgular, BİST’teki firmaların KFK sırasında kredi arzının azalması ve dış fonlama maliyetlerinin de artmasından dolayı daha fazla nakit stoku kullanmaları neticesinde, kriz ve sonrasında nakit varlıklarının ayarlama hızının arttığını göstermektedir. Genel bir sonuç olarak, firma sahipleri ve yöneticileri, krizler gibi yüksek belirsizlik ortamlarında kurumsal finansmanı etkileyen faktörleri de göz önünde bulundurarak ve nakit tutmanın maliyetini hesaba katarak, firmaları için doğru nakit tutma politikası belirlemelidirler.Öğe Küresel finansal krizin araştirma-geliştirme harcamalari ayarlama hizi üzerindeki etkisi(2021) Tekın, Hasan; Polat, Ali YavuzAmaç: Verimlilik artışını uzun vadede etkileyen Araştırma-Geliştirme (Ar-Ge) yatırımları hem şirketler hem\rde ülkeler düzeyinde son derece önemlidir. Küresel Finansal Kriz gibi ekonomik belirsizliğin arttığı bir\rdönemde firmaların yatırım kararları da bu belirsizlikten etkilenmektedir. Bu çalışmanın amacı, 2008-2009\rKüresel Finansal Krizinin Borsa İstanbul’da listelenen şirketlerin, Ar-Ge harcamalarının ayarlama hızlarını\rnasıl değiştirdiğini analiz etmektir.\rYöntem: Veri seti Thomson Reuters Datastream veri tabanından yıllık olarak çekilmiştir. Firma düzeyinde\roluşturulan panel veri 908 şirket-yılını kapsamaktadır. Geliştirilmiş Momentler Metodu (GMM) yardımıyla\riçsellik problemi en aza indirgenmeye çalışılmıştır.\rBulgular: 2003-2018 yılları için şirketlerin Ar-Ge harcamaları ayarlama hızlarının nispeten yavaş olduğu\rgörülmüştür. Bununla birlikte, şirketler Küresel Finansal Kriz sonrasında Ar-Ge harcamaları ayarlama\rhızlarını artırmışlardır. Genel olarak, zaman içinde Ar-Ge harcamalarını optimal bir düzeye getirmek isteyen\rşirket sahipleri ve yöneticileri ayarlama maliyetlerini ve belirsizliğin arttığı finansal krizleri göz önünde\rbulundurmalıdırlar.\rÖzgünlük: Bu çalışma Borsa İstanbul’da listelenen şirketlerin ilk kez Ar-Ge ayarlama hızlarını hesaplayarak\rkriz dönemi gibi belirsizlik dönemini de kapsayarak literatüre katkıda bulunmaktadır.\rÖğe Whether and when did bitcoin sentiment matter for investors? Before and during the COVID-19 pandemic(Springer, 2023) Aysan, Ahmet Faruk; Mugaloglu, Erhan; Polat, Ali Yavuz; Tekin, HasanUsing a wavelet coherence approach, this study investigates the relationship between Bitcoin return and Bitcoin-specific sentiment from January 1, 2016 to June 30, 2021, covering the COVID-19 pandemic period. The results reveal that before the pandemic, sentiment positively drove prices, especially for relatively higher frequencies (2-18 weeks). During the pandemic, the relationship was still positive, but interestingly, the lead-lag relationship disappeared. Employing partial wavelet tools, we factor out the number of COVID-19 cases and deaths and the Equity Market Volatility Infectious Disease Tracker index to observe the direct relationship between a change in sentiment and return. Our results robustly reveal that, before the pandemic, sentiment had a positive effect on return. Although positive coherence still existed during the pandemic, the lead-lag relationship disappeared again. Thus, the causal relationship that states that sentiment leads to return can only be integrated into short-term trading strategies (up to six weeks frequency).
