Abdullah Kürşat Merter

The identification of corporate financial distress using accounting information is adversely affected by high inflation because the information quality of accounting ratios decreases significantly during rapid changes in price levels. Therefore, decision makers require non-monetary warning signals that can provide relevant information without being affected by inflationary noise. In this study, we develop an explainable early-warning system by combining a formative Board Governance Capacity Index (BGCI) with eight accounting ratios to evaluate non-financial companies listed on Borsa Istanbul. We collected company data for the period 2014–2023, comprising 1,642 firm-year observations from 190 firms. Financial distress is defined as the presence of qualified or adverse audit opinions or negative book equity. The BGCI consists of five publicly reported dimensions: board size, board independence, percentage of female directors, percentage of foreign directors, and external audit quality. We evaluate the performance of six machine learning classifiers using firm-grouped cross-validation, isotonic probability calibration, out-of-time evaluation, and TreeSHAP for feature attribution. Incorporating BGCI improves out-of-sample performance for all six classifiers, with the AUC of the benchmark logistic regression model increasing by 0.067 points, from 0.644 to 0.711, and the calibrated Brier score decreasing by 0.054. Component ablation analysis confirms that BGCI performs better than individual governance attributes. BGCI has the highest mean out-of-sample Shapley value among the nine predictors (0.696) and increases the pooled out-of-time AUC from 0.671 to 0.719. Fixed-effects logistic regression estimates controlling for firm size, sector, and year effects indicate that a one-unit increase in BGCI is associated with a 4.3-percentage-point reduction in the predicted probability of financial distress. Partitioning predictions by macroeconomic regime indicates that the additional AUC gain provided by BGCI increases significantly from 0.016 during periods of relatively low inflation to 0.118 during periods of relatively high inflation, thereby improving the accuracy of early-warning signals when conventional accounting-based signals become less reliable.

Top executive narcissism is a crucial yet often overlooked concept in ESG performance. Current research primarily focuses on CEO narcissism, offering an incomplete view by largely ignoring the Board Chair's key role in shaping ESG outcomes. Furthermore, there is a notable lack of a comprehensive narcissism index, which would surpass the limitations of single‐ or limited‐indicator measures typically used in previous studies. To deepen understanding, this study empirically examines the distinct effects of narcissism exhibited by both the CEO and the Board Chair on a firm's environmental, social, and governance (ESG) pillars. By analyzing executive narcissism states in integrated report narratives alongside ESG data for 255 publicly listed companies from 2018 to 2023, measured via Refinitiv Eikon scores, this study shows that Board Chair narcissism is positively related to environmental and social performance but negatively related to governance performance. Conversely, CEO narcissism is positively associated with both environmental and governance performance but negatively associated with social performance. The varying effects across ESG dimensions indicate that narcissistic leadership depends on the executive's role and the stakeholder domain involved. This study advances upper echelons theory, the concept of narcissistic personality, and stakeholder theory by revealing the complex interactions among various executive narcissistic states and emphasizing the need to recognize these dynamics. Additionally, the findings offer practical insights into board composition and executive hiring to support sustainable business strategies.

Corporate governance certification provides a public assessment of organizational practices. Previous research has primarily examined the relationship between certification and firm outcomes, while the timing of certification adoption represents a distinct prediction problem. This study examines whether the first observed appearance on a governance rating list and subsequent rating upgrades can be predicted using statutory accounting disclosures. Rating history is also incorporated into the upgrade model. The institutional setting is the Borsa Istanbul Corporate Governance Index, where licensed agencies evaluate four governance sections and eligibility is determined by published thresholds. The dataset combines rating records for 49 non-financial firms from 2013 to 2024 with financial statements from 438 listed non-financial firms. Two interpretable modeling modules employ an out-of-time design, with predictor variables measured before the corresponding outcomes. The entry module compares L2-regularized logistic regression, Firth-penalized logistic regression, and gradient-boosted trees within a discrete-time hazard specification. The trajectory module estimates next-year rating upgrade scores for rated firms using accounting information and rating history. Both linear entry models achieve areas under the receiver operating characteristic (ROC) curve above 0.50, while the regularized logistic model shows a small positive difference in average precision relative to the training-prevalence benchmark. A single deflated firm-size measure provides discriminatory performance comparable to that of the multivariate entry models. The combined upgrade models achieve ROC areas close to 0.60, while models incorporating rating history achieve higher ROC areas than accounting-only models. Feature attributions also differ between the two tasks, with firm size playing a prominent role in entry predictions and rating history contributing more strongly to upgrade predictions. These findings identify the information sets associated with observed rating adoption and progression. The proposed framework provides rankings of candidate firms and feature-level explanations to support governance monitoring and outreach planning.

Bu çalışma, gelişmekte olan piyasalarda kurumsal yönetişim mekanizmalarının yetersizliğinin yöneticilerin kaynak tahsis kararlarını nasıl etkilediğini yatırım yapışkanlığı çerçevesinde incelemektedir. Araştırmanın temel sorunsalı, yöneticilerin serbest nakit akışlarını kişisel çıkarları doğrultusunda kullanmalarının, sermaye harcamalarında asimetrik bir davranış kalıbına yol açıp açmadığıdır. Bu amaçla, 2005-2024 döneminde Borsa İstanbul'da işlem gören imalat, hizmet ve teknoloji firmalarına ait 3,100 firma-yıl gözleminden oluşan dengesiz bir panel veri seti kullanılmıştır. Ekonometrik analizlerde, potansiyel değişen varyans ve yatay kesit bağımlılığı sorunlarını kontrol altına alan Driscoll-Kraay dirençli standart hatalara sahip çift yönlü sabit etkiler modeli tercih edilmiştir. Ampirik bulgular, firmaların nakit akışlarındaki artışlara agresif yatırımlarla yanıt verirken, nakit daralmaları karşısında yatırımları kısmakta belirgin bir direnç gösterdiğini kanıtlayarak yatırım yapışkanlığının varlığını doğrulamaktadır. Alt örneklem analizleri, bu asimetrik davranışın beklentilerin aksine finansal kısıtlar altındaki düşük serbest nakit akışına sahip firmalarda daha şiddetli olduğunu ortaya koymuştur. Bulgular bir arada değerlendirildiğinde, BİST firmalarında asimetrik yatırım davranışının temel kaynağının imparatorluk kurma güdüsünden çok finansal kısıtlar ve piyasaya zayıflık sinyali vermekten kaçınma kaygısı olduğu anlaşılmaktadır. Bu sonuçlar, yönetim kurullarının yatırım projeleri için nesnel zarar kesme mekanizmaları oluşturmasının ve düzenleyicilerin sermaye harcamalarına ilişkin ifşa standartlarını güçlendirmesinin gerekliliğini ortaya koymaktadır.

This study investigates impact of corporate sustainability mechanisms on the Environmental, Social, and Governance (ESG) performance of firms listed on the Borsa Istanbul (BIST) Sustainability Index. Using an unbalanced panel dataset of 260 firm-year observations from 51 unique companies between 2014 and 2023, this research examines how the establishment of a board-level sustainability committee, the adoption of the Global Reporting Initiative (GRI) standards for sustainability reports, and the external assurance of these reports influence ESG scores. Furthermore, the study explores the moderating role of multinational status in the relationship between a composite measure of these sustainability mechanisms and ESG performance. The empirical analysis is conducted using a fixed-effects panel regression model with Driscoll-Kraay standard errors to address potential issues of heteroskedasticity, autocorrelation, and cross-sectional dependence. The findings reveal that the presence of a sustainability committee, adherence to GRI standards, and obtaining external assurance for sustainability reports are all positively and significantly associated with higher ESG performance. A composite index of these mechanisms also demonstrates a significant positive impact. Notably, the results indicate that multinational status positively moderates this relationship, suggesting that the effect of robust sustainability governance structures on ESG performance is more pronounced for multinational corporations. These findings offer valuable insights for policymakers, investors, and corporate managers by highlighting the importance of institutionalized sustainability governance and reporting practices in enhancing corporate ESG outcomes, particularly within the context of an emerging market.

Despite the growing emphasis on corporate sustainability, it remains unclear whether firms will align with common ESG standards. The Phillips–Sul convergence methodology, in combination with dynamic time‐warping clustering, was utilized to analyze the ESG trajectories of 430 S&P 500 firms from 2019 to 2024. Contrary to the prevailing expectation of universal convergence, we identify five distinct convergence clubs that transcend traditional industry boundaries, with clustering primarily based on ESG risk levels. While the utilities and real estate sectors exhibit internal convergence due to regulatory pressures, the formation of cross‐sector clubs is driven by shared sustainability challenges. It is evident that environmental performance converges within industries, social dimensions cluster by risk profiles, and governance shows uniform patterns across sectors. These findings extend the scope of convergence theory to corporate sustainability contexts, thereby revealing that institutional pressures, stakeholder configurations, and resource capabilities create multiple equilibria rather than single standards. The multi‐method approach utilized in this study provides robust evidence that risk‐based convergence dominates sector‐based patterns. The result offers novel insights for sustainable finance strategies and regulatory design.

Purpose: This study investigates the relationship between CEO narcissism and greenwashing in integrated reports, focusing on differences between the banking and non-banking sectors under different regulatory conditions. Design/methodology/approach: This study used Bidirectional Encoder Representations from Transformers (BERT)–based text analysis on 105 Turkish firms to create a CEO narcissism and greenwashing index, identifying trends in CEO narcissism and corporate greenwashing across the banking and non-banking sectors from 2020 to 2023. Then, a fuzzy-set qualitative comparative analysis was applied to explore configurational pathways and complex combinations of CEO narcissism variables that lead to the greenwashing index, with hierarchical regression analysis used for econometric validation. Findings: This study identified a clear link between CEO narcissism and greenwashing in integrated reports. Additionally, it showed that the connection between CEO narcissism and greenwashing changes over time and differs across sectors. While non-banking firms initially exhibited higher levels of CEO narcissism and greenwashing, banks surpassed them by 2023, despite stricter regulations. This shift indicates that regulation may not stop greenwashing but instead shape its form and visibility. Moreover, the study highlighted that different configurations of CEO narcissism have varied impacts on greenwashing across sectors, offering a better explanation of corporate greenwashing than traditional regression analysis. Research limitations/implications: This study is limited to a single-country context and relies on secondary data from integrated reports, which may not fully reflect internal sustainability practices. Practical implications: This study emphasized the need for sector-specific regulatory mechanisms and independent verification systems to combat sophisticated greenwashing tactics, especially in heavily regulated banking environments, where narcissistic leadership exploits compliance frameworks to boost its reputation. Originality/value: This study introduced a comprehensive six-dimensional narcissism framework and demonstrated how executive psychological traits interact with institutional contexts through configurational analysis. The research expands upper echelons and stakeholder theory by uncovering sector-specific contingencies in narcissism-greenwashing links, challenging traditional views on regulatory effectiveness while adopting innovative methods that combine fuzzy logic with multidimensional measurement models.

Rekabetçi küresel pazar ortamında faaliyet gösteren işletmelerin sürekliliği için en kritik faktör olan hizmet kalitesi, müşteri memnuniyetine ve yüksek karlılığa ulaşmada belirleyici role sahiptir. Dolayısıyla, müşteri odaklı yaklaşımı benimseyen firmalar açısından hizmet kalitesi ve müşteri memnuniyetinin düzenli olarak ölçülmesi ve takip edilmesi stratejik bir gereklilik olarak öne çıkmaktadır. Bu çalışma, muhasebe firmalarının hizmet kalitesinin müşteri memnuniyeti ve sadakati üzerindeki etkilerini SERVQUAL modeli kullanarak incelemeyi amaçlamaktadır. Muhasebe hizmeti kullanan 420 paydaştan (işletme sahipleri/ortakları, yöneticiler ve çalışanlar) anket yöntemiyle toplanan veriler Yapısal Eşitlik Modellemesi ile analiz edilmiştir. Araştırma bulguları, hizmet kalitesinin tüm boyutlarının müşteri memnuniyeti üzerinde istatistiksel olarak anlamlı ve pozitif etkiye sahip olduğunu ortaya koymuştur. Benzer şekilde, müşteri memnuniyetinin müşteri sadakatini anlamlı düzeyde etkilediği tespit edilmiştir. Hizmet kalitesi boyutlarından fiziksel özellikler dışındaki dört boyutun müşteri sadakati üzerinde istatistiksel olarak anlamlı ve pozitif etkisi bulunmaktadır. Ayrıca, müşteri memnuniyetinin hizmet kalitesi ile müşteri sadakati arasındaki ilişkide kısmi aracılık etkisi gösterdiği belirlenmiştir.