İŞLETME İÇİ SUİİSTİMALİN TESPİTİNDE MAKİNE ÖĞRENMESİNİN ROLÜ

Öz

Kurumları tehdit eden önemli operasyonel risklerden biri de iç suiistimaldir. Söz konusu eylemleri önleyici proaktif kontrollerin varlığı kadar, hızlı bir şekilde tespit edilmesini sağlayacak reaktif sürekli izleme mekanizmalarının mevcudiyeti de önem arz etmektedir. İlk çalışmamızın (Temuçin et al., 2021) devamı niteliğinde olan bu makalemizde, Türkiye’nin önemli bankalarından biri olan Garanti BBVA’nın iç suiistimal tespitinde büyük veri dönüşüm hikayesini bir adım daha ileriye taşıyoruz. “Kural-bazlı” olarak nitelendirilen ve başarısını kanıtlamış mevcut tespit yaklaşımına, biriken veri havuzu sayesinde makine öğrenmesinin nasıl entegre edildiğinden bahsedeceğiz. Makine öğrenmesiyle desteklenen yeni hibrid modelle; daha etkin bir sürekli izleme yaklaşımı kurulduğu gibi, yüksek iç suiistimal tespit oranı ve düşük Banka kaybı gibi kritik göstergelerde de yıllara sari sürdürülebilirlik kazanmak mümkün olmuştur. İç suiistimalin tespitinde başarısını kanıtlayan ve makine öğrenmesinin entegre edildiği güncel metodolojimizin sektöre de ilham kaynağı olmasını umuyoruz.

Anahtar Kelimeler

• İç suiistimal
• Büyük veri
• Makine öğrenmesi
• XGBoost

ROLE OF MACHINE LEARNING IN INTERNAL FRAUD DETECTION

Öz

One of the operational risks faced by the entities is internal fraud. In addition to preventive proactive controls, the existence of reactive continuous risk monitoring to quickly detect them is of great importance. In this paper written as the continuation of our first study (Temuçin et al., 2021), we take one step further the big data transformation story of Garanti BBVA - one of the most important banks of Türkiye - regarding detection of internal frauds. We will explain how machine learning was integrated into the “rule-based” approach with proven success thanks to the accumulated data pool. The hybrid model supported with machine learning has established a more effective continuous monitoring approach and also ensured the maintenance of sustainable critical metrics such as high internal fraud detection ratio and low Bank loss. We hope that our current methodology with proven success in detection of internal frauds and with its recent integration with machine learning will be an inspiration for the sector.

Anahtar Kelimeler

• Internal fraud
• Big data
• Machine learning
• XGBoost

Kaynakça

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