Data Science: The Game Changer in Modern Finance

fintech
fintech
data science
data science

Jan 15, 2025

Kateryna Bilyk

Imagine a bank that not only knows its clients' needs but can also predict them. In today’s digital-first world, Data Science transforms this vision into reality. From instantly spotting fraudulent transactions to suggesting the right financial products, advanced data tools are helping banks become more insightful, responsive, and forward-thinking.

In this article, we’ll dive into some of the most critical challenges banks face today—like fraud detection, risk assessment, customer segmentation and personalized recommendations — and show how Data Science is changing the game. With smart algorithms and powerful machine learning tools, banks can now unlock insights from data to make decisions that are faster and smarter than ever before.

1. Risk Scoring and Management in Fintech

"The future belongs to those who prepare for it today." — Malcolm X

Problems

In the fintech sector, effective risk management is crucial for minimizing financial losses and mitigating the effects of market volatility. Key challenges include:

  • Estimating the likelihood of user default: Traditional models often miss behavioral nuances, increasing the risk of lending to high-risk individuals.

  • Determining optimal credit limits: Incorrectly assigned credit limits can expose institutions to risk or negatively impact customer satisfaction.

  • Evaluating high-risk users: Without robust data insights, assessing high-risk users becomes difficult, leaving institutions vulnerable to defaults.

  • Predicting unsettled transactions: Late settlements can disrupt liquidity, and predictive models help maintain smoother financial operations.

As the complexity of financial transactions increases, there's a pressing need for more dynamic and accurate risk assessment approaches that can adapt to new information in real-time. By leveraging advanced data science techniques, banks can better anticipate and mitigate these risks, safeguarding their assets and maintaining customer trust.

Data Types

In the financial sector, a variety of data types can be utilized to assess customer behavior, financial reliability, and risk. These data types - ranging from credit history to online activity - offer different perspectives on an individual’s financial standing, and when combined, they create a more comprehensive view that aids in more accurate decision-making.

Bureau Data:
  • What It Is: Bureau data includes credit history details such as payment records, outstanding debts, and credit inquiries. It’s often the foundation for traditional risk assessment and credit scoring.

  • Why It’s Effective: Bureau data provides a baseline measure of a customer’s financial reliability, helping to estimate creditworthiness. When combined with other data types, bureau data enhances the accuracy of risk scoring and overall financial decision-making.

Transaction Data:
  • What It Is: Transaction data encompasses customer spending habits, purchase patterns, and account usage, providing a detailed view of financial behavior over time.

  • Why It’s Effective:  By analyzing transaction data, businesses can gain insights into how customers manage their finances. Indicators like excessive spending or irregularities can signal financial instability, which may elevate risk levels.

Social Media Data:
  • What It Is: Social media data includes information derived from a customer’s online presence, such as posting frequency, professional affiliations, and social connections.

  • Why It's Effective: Social media behavior provides context to a customer's lifestyle and potential financial risks. For example, significant life changes (e.g., a new job or relocation) may affect their financial risk profile.

Telecom Data:
  • What It Is: Telecom data includes information about a customer’s mobile usage, such as call patterns, data consumption, payment behavior, and geographic mobility.

  • Why It’s Effective: Telecom data provides unique behavioral insights, such as call patterns and data usage, which can indicate lifestyle trends or significant changes. For example, frequent location changes might suggest mobility or new opportunities, while shifts in usage patterns could signal evolving customer needs or potential risks.

Questionnaire Data: 
  • What It Is: Questionnaire data is self-reported information collected directly from customers, often focusing on spending habits, income, financial goals, and risk tolerance.

  • Why It's Effective: Unlike transactional or behavioral data, questionnaires can capture qualitative insights that reveal a customer’s true financial intentions and preferences. For instance, understanding financial goals and risk tolerance helps in designing tailored products and services. When building questionnaires, it’s essential to balance detail with user experience, ensuring that questions are clear and easy to answer.

Data Preprocessing

Data preprocessing is the crucial first step in preparing raw data for analysis and machine learning. It involves cleaning, transforming, and organizing data to improve model performance. Techniques like handling missing values, scaling numerical features, encoding categorical variables, and reducing dimensionality ensure the data is consistent and ready for training. Proper preprocessing enhances model accuracy, speeds up convergence, and reduces bias from outliers, leading to more reliable predictions.

Algorithms

To address credit scoring, the choice of algorithm largely depends on the nature of the available data and the specific approach you wish to take:

Logistic Regression
  • What It Is: Logistic Regression is a statistical algorithm used to predict binary outcomes (e.g., yes/no, 0/1) based on one or more independent variables. It models the probability of an event occurring by applying a logistic function, which outputs values between 0 and 1.

  • Why It's Effective: Logistic Regression is simple yet powerful for classification tasks, working well when the relationship between variables is linear (in terms of log-odds). It also provides interpretable outputs, showing the importance of each input feature and how factors influence predictions.


Decision Trees
  • What It Is: Decision trees are models that split data based on feature values. Each node tests a feature (e.g., income > $50,000) and each branch represents an outcome (e.g., default or no default). They are used for both classification (categorical outcomes) and regression (continuous outcomes).

  • Types: Classification Trees for categorical outcomes (e.g., predicting whether a customer defaults or not) and Regression Trees for continuous outcomes (e.g., predicting a customer’s credit score).

  • Why It's Effective: 

    • Interpretability: Easy to understand and explain.

    • Handles Non-Linear Data: Captures complex relationships, crucial for risk prediction.

    • Versatility: Works well with numerical, categorical data, and missing values.

Deep Neural Networks (DNNs)
  • What It Is: DNNs are AI models inspired by the brain's structure, with multiple layers of interconnected nodes (neurons) that process and transform data to identify complex patterns.

  • Why It’s Effective: DNNs excel at analyzing diverse data types, from structured (numerical and categorical) to unstructured (text, images). For risk prediction, DNNs can sift through massive datasets to uncover subtle, hard-to-detect patterns. For example, changes in customer communication patterns—such as increased calls to unfamiliar numbers—might indicate financial instability, which a DNN could identify early in the data.

Ensemble Models
  • What It Is: Ensemble methods combine multiple decision tree-based models to boost prediction accuracy. Examples include bagging (e.g., Random Forests) and boosting (e.g., XGBoost, LightGBM). These techniques enhance performance by leveraging different strategies to aggregate individual tree predictions.

    • Bagging: Trains multiple decision trees in parallel, each using a bootstrapped subset of the data samples, and averages their predictions to reduce variance and prevent overfitting.

    • Boosting: Builds decision trees sequentially, with each tree focusing on correcting the errors made by the previous ones, improving model accuracy over time.

  • Why It's Effective: Both bagging and boosting methods use decision trees as the base learners, improving model robustness and accuracy. Bagging reduces variance, making models more stable, while boosting helps focus on harder-to-predict data points, enhancing precision. These ensemble techniques are especially useful for tasks like credit scoring, customer behavior analysis, and risk prediction.

Other algorithms:

Metrics

In fintech, assessing risk accurately is crucial, especially for fraud detection and credit scoring. Choosing the right metrics ensures models effectively predict and manage risk. These metrics can be divided into two main categories

  • With Threshold: These metrics use a predefined cut-off point to classify outcomes. For example, in fraud detection, a threshold might be set to flag transactions above a certain likelihood of being fraudulent. These metrics are useful for decision-making tasks where clear classification is needed, like fraud detection or credit approval.

  • Without Threshold: These metrics provide continuous output, such as probabilities or scores, which can be interpreted without strict cutoffs. These are often used for modeling risk over time or estimating the likelihood of an event occurring, where a threshold may not be necessary for all use cases. The client could choose a threshold depending on the credit portfolio, which they have an amount of accepted risk level and profit estimated in their business model.

So both types of metrics are important as they help balance model accuracy and real-world application. Threshold-based metrics offer clear decision-making points, while non-threshold metrics offer more flexibility and nuanced insights.

2. Fraud detection

“Cybercrime is the greatest threat to every company in the world.” - Ginni Rometty.

Fraud detection is essential for financial institutions to protect assets and maintain customer trust. Machine learning helps identify fraud effectively by:

  • Spotting unusual transactions in real-time: Unlike traditional systems, machine learning can detect complex, evolving fraud patterns.

  • Detecting hidden fraud networks: Network analysis uncovers fraudulent connections between accounts.

  • Reducing unnecessary alerts: Predictive models help reduce the number of alerts triggered by legitimate transactions, ensuring only truly suspicious activities are flagged.

  • Adapting to emerging fraud tactics: Machine learning learns from new data to identify evolving fraud strategies.

Fraud Types

Fraud comes in many forms, far beyond the common examples like phishing. Each type requires a tailored approach to detection and prevention, as fraudsters continually adapt their methods. The following illustration highlights different types of fraud:

Algorithms

Anomaly Detection
  • What It Is: Anomaly detection identifies unusual patterns in transaction data using machine learning models like Isolation Forests, One-Class SVM, and Autoencoders to flag deviations from normal behavior.

  • Why It’s Effective:  It’s great for spotting new fraud types by isolating outliers. For example, a sudden large transaction on an account that usually makes small payments might indicate fraud.

  • Example: Isolation Forest models analyze millions of transactions and flag ones that don’t match typical spending patterns, such as a customer suddenly making multiple overseas purchases.

Network analysis
  • What Is It:  Network analysis examines relationships between entities in a dataset to detect fraud, using graph-based approaches to model connections between accounts, transactions, and behaviors.

  • Why It’s Effective: It uncovers hidden fraud rings and collusion by identifying patterns in transactions that traditional methods might miss. For example, multiple accounts with shared transaction patterns could indicate coordinated fraud.

  • Example: Graph algorithms can detect clusters of suspicious transactions, like frequent small transfers between users, suggesting collusion or fraud. Graph Neural Networks (GNNs) can further enhance detection by learning from relational data.

Chatbot Fraud Detection
  • What Is It: Chatbot fraud detection uses AI-driven chat interfaces to monitor user interactions for signs of fraud by analyzing language patterns and requests.

  • Why It’s Effective: Chatbots can instantly recognize and respond to unusual inquiries or phishing attempts, preventing sensitive information from being disclosed.

  • Example: Here is one story of how a Nigerian bank used an AI chatbot to prevent fraud by analyzing customer interactions for language that indicated scam attempts, such as requests for sensitive data or odd transaction patterns. When the chatbot detected suspicious requests—like those resembling phishing—it flagged them and prevented disclosure of private information, thereby protecting customers from potential fraud.

Transaction Monitoring
  • What It Is: Real-time analysis of transactions to identify suspicious activities, tracking metrics like transaction amount, location, and user behavior using rules-based filters and machine learning models.

  • Why It’s Effective: Transaction monitoring allows instant detection of fraud, reducing financial losses and enabling quick response to threats.

  • Example: A bank’s system flags a typically local shopper's account when they suddenly make a large international transfer, triggering an alert based on unusual spending patterns. This proactive approach helps prevent account takeovers, cross-border fraud, and money laundering.

Behavioral Biometrics
  • What It Is: Behavioral biometrics analyzes patterns like typing speed, mouse movements, and device handling to verify identity and detect fraud.

  • Why It’s Effective: Even with stolen credentials, fraudsters struggle to replicate unique behavioral patterns, making this method effective in spotting unauthorized activity.

  • Example: By tracking user interactions, such as typing speed and mouse movements, behavioral biometrics can flag suspicious actions. For instance, if a user’s typing pattern changes significantly, the system can trigger a security check, offering an additional layer of protection.

Challenges

3. Customer analytics

  • What It Is: Customer analytics involves collecting, analyzing, and interpreting customer data to better understand their behaviors, preferences, and needs. This process provides actionable insights that can improve decision-making across various business areas, such as marketing, product development, and risk management.

  • Why It’s Important: Customer analytics helps businesses thrive by tailoring products to individual needs, uncovering opportunities for cross-selling, improving risk management, and optimizing personalized marketing strategies.

  • Techniques:

    1. Predictive Analytics: Uses historical data to forecast future behaviors or outcomes. For example, predicting the likelihood of a customer defaulting on a loan.

    2. Descriptive Analytics: Focuses on summarizing historical data to identify trends and patterns. For example, analyzing past transactions to determine average customer spending.

    3. Prescriptive Analytics: Provides recommendations for the best course of action based on data insights. For example, suggesting personalized financial products based on a customer’s profile.

    4. Behavioral Analysis: Examines customer habits and actions to understand their motivations. For example, tracking shopping cart abandonment rates to refine the checkout process.

    5. Causal Analysis: Investigates cause-and-effect relationships between different factors. For example, determining how changes in pricing affect customer purchasing decisions or how marketing campaigns influence customer retention

4. Customer segmentation

 "The aim of marketing is to know and understand the customer so well the product or service fits him and sells itself."  - Peter Drucker.

illustration from: https://hkaift.com/clustering-techniques-in-fintech-applications-and-prospect/

Illustration from AIFT

Customer segmentation divides a customer base into groups based on demographics, behaviors, or financial needs, allowing companies to tailor their products and services more effectively. Segmentation enables personalized marketing and product offerings, improving customer engagement and satisfaction. By analyzing user data, companies can also manage risks better—for example, by customizing loan terms to suit individual customer profiles.

Algorithms

K-Means Clustering
  • What It Is: K-Means divides customers into groups based on similarity, assigning each customer to the cluster with the closest "centroid" (center point).

  • Why It's Effective: Efficient for large datasets with clear clusters. K-Means works well for segmenting data that can naturally split into groups, like transaction patterns.

  • Example: Segmenting customers into groups like “frequent shoppers” and “occasional buyers” based on how often they make purchases.

Decision Trees
  • What It Is:  A decision tree uses a series of “if-then” rules to split data into branches, helping classify customers based on attributes like age, income, or spending.

  • Why It's Effective: Great for interpretability, decision trees model complex rules and are particularly useful for binary segmentation, such as assessing risk.

  • Example: Customers with high credit scores could be classified as “low risk” for loans, while those with low scores are “high risk.”

DBSCAN (Density-Based Spatial Clustering of Applications with Noise)
  • What It Is: DBSCAN identifies groups based on data density, allowing it to find irregularly shaped clusters and distinguish outliers.

  • Why It's Effective: Ideal for spotting outliers and rare customer behaviors, which can highlight unique opportunities.

  • Example: Identifying customers with rare behaviors, like high-value but infrequent transactions, which may indicate they’re valuable for personalized services.

Hierarchical Clustering
  • What It Is: Hierarchical clustering builds a tree of customer relationships, starting with each customer as an individual cluster and merging them step-by-step.

  • Why It's Effective: Creates a flexible hierarchy, making it easy to adjust how granular or general the segmentation is.

  • Example: A top-level segment may be “budget-conscious,” which could break down into sub-segments like “low-risk investors” and “high-interest savings seekers.”

Node2vec Embedding for Enhanced Segmentation
  • What It Is: Node2vec is a technique that generates embeddings (representations) of nodes (e.g., customers) within a network, based on their relationships or connections. It captures both global and local patterns in a network, making it ideal for representing complex customer relationships and behaviors in a concise form.

  • Why It’s Effective: When customer data includes relational aspects—such as connections between users in a network or transaction patterns—node2vec can transform these into rich features that enhance segmentation models. These embeddings can then be used as input to clustering algorithms (like K-Means or DBSCAN) or other segmentation approaches, providing more accurate and insightful grouping by capturing underlying network patterns.

  • Example: In a financial services context, node2vec could model relationships between customers based on shared accounts, transaction histories, or social connections. The resulting embeddings would help segment customers into more meaningful groups, potentially uncovering high-value networks or identifying communities with similar financial behaviors.

5. Product recommendations

“We see our customers as invited guests to a party, and we are the hosts. It’s our job every day to make every important aspect of the customer experience a little bit better.” - Jeff Bezos.

Problem

Customers often struggle to find financial products that suit their needs, resulting in missed opportunities for banks and financial institutions to cross-sell or upsell products. Without personalized recommendations, engagement, conversions, and customer satisfaction suffer, leading to less profitable relationships.

Algorithms

Content-Based Filtering
  • What It Is: Recommends items based on the features of content. For example, if a user explores mortgage options, the system analyzes their attributes (e.g., interest rates, terms) and suggests similar products.

  • Why It's Effective: Focuses on content similarity, ensuring recommendations align with the user’s demonstrated interests.

  • Example: Looking at fixed-rate mortgages might lead to suggestions for refinancing or home equity loans with similar conditions.

Collaborative Filtering
  • What It Is: Analyzes the behavior of multiple users to identify similarities and recommend products. It relies on data from other users' interactions with financial products.

  • Why It's Effective:  It uncovers hidden patterns by leveraging collective insights from users with similar behaviors, offering diverse and personalized suggestions.

  • Example: A user who frequently interacts with savings accounts might be recommended credit card products favored by other users with similar savings behaviors.

Hybrid Recommendation System
  • What It Is: Combines both content-based and collaborative filtering to integrate the strengths of both methods. It uses a mix of user preferences, behaviors from similar users, and item attributes.

  • Why It's Effective: Overcomes the limitations of each method individually, providing more accurate, diverse, and personalized recommendations.

  • Example: A financial institution could combine a user’s past product usage with trends from other users with similar financial goals to recommend tailored loans or investment products.

Personalized AI-advisor
  • What It Is:  Algorithms that provide personalized financial product recommendations based on an individual’s preferences, risk tolerance, and financial goals. These systems adapt and improve over time, learning from customer interactions and market conditions.

  • Why It's Effective: AI-advisors are scalable, cost-efficient, and provide personalized advice, making financial planning more accessible.

  • Example: An AI-advisor might suggest a retirement plan to a user based on their age, income, and long-term goals.

Multi-objective Optimization Ranking
  • What It Is: A model that ranks product recommendations by optimizing multiple objectives, such as user preferences, product profitability, and market demand, to ensure the best balance across several goals.

  • Why It's Effective:  It maximizes the utility of recommendations by considering multiple factors simultaneously, ensuring that suggestions align with both user needs and business objectives.

  • Example:  A fintech company could recommend a premium loan product that not only aligns with the user’s preferences (e.g., low interest rate or flexible terms) but also takes into account the profitability of the product for the institution. For instance, it could prioritize recommending a slightly more expensive loan with a higher interest rate, as long as it matches the customer’s financial profile and goals, ensuring both the customer’s satisfaction and the company’s profitability.

Final words

Data Science has undeniably revolutionized the financial sector, enabling more informed decision-making, improving risk management, and enhancing customer personalization. As we continue to refine our models and algorithms, the potential for further optimization is immense.

As the industry evolves, it will be crucial for organizations to stay ahead of the curve by embracing innovative techniques while maintaining a focus on transparency, fairness, and continuous improvement. The future of finance is data-driven, and Data Science is the key to unlocking its full potential.