Quick Learnology

Application of Machines Learning in Banking and Securities​

Machine learning has become an integral part of the banking and securities industry in recent years. It is being used in various applications, such as fraud detection, customer data management, personalized marketing, credit risk analysis, and more. In this response, I will discuss some of the ways machine learning is being used in the banking and securities industry.

Fraud Detection:

Machine learning is being used in fraud detection to identify suspicious transactions and prevent fraudulent activities. Rule-based and machine learning-based approaches are being used to detect anomalies in transactions. Machine learning algorithms are trained on large datasets to learn patterns of fraudulent activities and flag any suspicious transactions.

Customer Data Management:

Machine learning algorithms are used to manage customer data by identifying patterns in customer behavior, which can be used to improve customer service and customer experience. Customer data is analyzed using machine learning algorithms to identify trends and insights that can be used to make better decisions.

Personalized Marketing:

Machine learning is used to personalize marketing efforts by analyzing customer data and creating targeted campaigns. Machine learning algorithms are used to segment customers based on their behavior and interests, allowing marketers to create personalized campaigns that are more effective.

Credit Risk Analysis:

Machine learning is being used to analyze credit risk by predicting the likelihood of loan default. Machine learning algorithms analyze large datasets to identify patterns and predict the probability of loan default, allowing banks to make more informed decisions.

Imbalance Data Handling:

Imbalanced data is a common problem in the banking and securities industry, where the number of fraudulent transactions is significantly smaller than the number of legitimate transactions. Machine learning algorithms such as Over Sampling, Under Sampling, and SMOTE are being used to handle imbalanced data.

Credit Card Fraud Detection:

Machine learning algorithms such as Logistic Regression, Decision Tree, Random Forest, and Gradient Boosting are being used to detect credit card fraud. These algorithms are trained on large datasets to learn patterns of fraudulent activities and flag any suspicious transactions.

Case Study of Fraud Detection:

Many research papers have been published on fraud detection in the banking and securities industry. These papers discuss various machine learning algorithms and techniques used for fraud detection. Implementation of these techniques in real-world scenarios has resulted in improved fraud detection and prevention.

In conclusion, machine learning is being widely used in the banking and securities industry to improve various aspects of the business, including fraud detection, customer data management, personalized marketing, and credit risk analysis. With the increasing availability of data and computing power, the use of machine learning is expected to increase further in the future.

Rule-based and machine learning-based approach in fraud detection

Fraud detection in banking and finance can be approached in two ways: rule-based and machine learning-based.

Rule-based fraud detection involves setting up a set of rules that define normal and abnormal behavior. Transactions that deviate from these rules are flagged as suspicious and investigated. This approach is based on a priori knowledge and is effective in detecting known types of fraud. However, it can be limited in its ability to detect new and previously unknown types of fraud.

Machine learning-based fraud detection, on the other hand, involves training algorithms on large datasets of transactional data to identify patterns and anomalies that indicate fraudulent activity. These algorithms can learn to detect previously unknown types of fraud and can adapt to new types of attacks. Machine learning-based fraud detection can also help reduce false positives and improve accuracy over time.

A hybrid approach that combines both rule-based and machine learning-based fraud detection can also be used, where rule-based systems are used to flag suspicious transactions based on predefined rules, and machine learning algorithms are used to refine the results and identify new types of fraud.

Overall, both rule-based and machine learning-based approaches have their advantages and disadvantages. Rule-based systems are effective in detecting known types of fraud but can be limited in their ability to detect new types of fraud. Machine learning-based systems are more flexible and adaptive, but can require large amounts of data to train and can be less transparent in their decision-making process. A hybrid approach can combine the strengths of both approaches and provide an effective and efficient fraud detection system.

AI in banking and finance

Artificial intelligence (AI) is becoming an increasingly important tool in the banking and finance industry, offering a range of benefits such as improved efficiency, better decision-making, and enhanced customer service. Here are some of the key areas in which AI is being used in banking and finance:

  1. Fraud Detection: AI algorithms can analyze large volumes of transactional data and identify patterns and anomalies that indicate fraudulent activity, helping to prevent financial losses and maintain customer trust.
  2. Customer Service: AI-powered chatbots can provide customers with personalized recommendations and assistance, reducing the workload on human customer service representatives and improving response times.
  3. Risk Management: AI can be used to analyze market data and identify potential risks, such as credit risk or market risk. This helps financial institutions to make more informed decisions about lending and investments.
  4. Trading and Investment: AI algorithms can be used to analyze market data and make predictions about future trends, helping banks and other financial institutions to make more profitable investments and trades.
  5. Loan Underwriting: AI algorithms can analyze customer data and determine creditworthiness, helping banks to make better decisions about lending and reduce default rates.
  6. Compliance and Regulation: AI can be used to ensure that banks and other financial institutions are meeting regulatory requirements and prevent legal and reputational risks.
  7. Personalization and Customer Segmentation: AI algorithms can be used to analyze customer data and segment customers based on their behavior and preferences, allowing financial institutions to offer personalized products and services.

Overall, AI is transforming the banking and finance industry by improving efficiency, reducing risks, and enhancing customer service. As AI technology continues to evolve and become more sophisticated, we can expect it to play an even greater role in this industry in the coming years.

Credit Card Fraud Detection using different machine learning classifier

Credit card fraud detection is an important problem that many financial institutions and businesses face. Machine learning algorithms can be used to automatically detect fraudulent credit card transactions by analyzing transaction data and identifying patterns and anomalies.

There are several different machine learning classifiers that can be used for credit card fraud detection, including:

  1. Logistic Regression: This algorithm is often used for binary classification problems and can be effective for detecting credit card fraud. Logistic regression can help identify patterns in the data and make predictions about whether a transaction is fraudulent or not based on those patterns.
  2. Decision Trees: Decision trees are a type of algorithm that uses a tree-like structure to classify data. In credit card fraud detection, decision trees can be used to identify which features of a transaction are most indicative of fraud.
  3. Random Forest: Random forest is an ensemble learning algorithm that uses multiple decision trees to classify data. In credit card fraud detection, random forest can be used to improve the accuracy of predictions by combining the predictions of many different decision trees.
  4. Support Vector Machines (SVM): SVM is a powerful machine learning algorithm that is often used for classification problems. In credit card fraud detection, SVM can be used to identify patterns in the data and classify transactions as fraudulent or non-fraudulent based on those patterns.
  5. Neural Networks: Neural networks are a type of machine learning algorithm that are modeled after the structure of the human brain. In credit card fraud detection, neural networks can be used to analyze transaction data and identify patterns that are indicative of fraud.

Implementation

Here is a high-level implementation of credit card fraud detection using different machine learning classifiers:

  1. Data Preparation: First, you need to prepare the data for analysis. This involves collecting and cleaning the data, handling missing values, and converting the data into a suitable format for analysis.
  2. Feature Selection: Next, you need to select the features that are most relevant for identifying fraudulent transactions. This may include features such as transaction amount, location, time of day, and type of transaction.
  3. Splitting Data: Split the data into training and testing sets. The training set will be used to train the machine learning models, while the testing set will be used to evaluate the performance of the models.
  4. Model Selection: Choose the machine learning classifiers to use for the task at hand. As discussed earlier, this can include logistic regression, decision trees, random forest, SVM, or neural networks.
  5. Model Training: Train the chosen machine learning classifiers on the training data. This involves feeding the algorithms the input features and output labels (fraudulent or non-fraudulent), and allowing the algorithm to learn the patterns in the data.
  6. Model Evaluation: Evaluate the performance of the trained models using the testing data. This involves making predictions on the testing data and comparing those predictions to the true labels.
  7. Model Selection: Based on the evaluation results, select the best-performing model or combination of models for credit card fraud detection.
  8. Deployment: Finally, deploy the selected model(s) to automatically detect fraudulent transactions in real-time.
import pandas as pd # data processing
import numpy as np # working with arrays
import matplotlib.pyplot as plt # visualization
from termcolor import colored as cl # text customization
import itertools # advanced tools

from sklearn.preprocessing import StandardScaler # data normalization
from sklearn.model_selection import train_test_split # data split
from sklearn.tree import DecisionTreeClassifier # Decision tree algorithm
from sklearn.neighbors import KNeighborsClassifier # KNN algorithm
from sklearn.linear_model import LogisticRegression # Logistic regression algorithm
from sklearn.svm import SVC # SVM algorithm
from sklearn.ensemble import RandomForestClassifier # Random forest tree algorithm
from sklearn.metrics import confusion_matrix # evaluation metric
from sklearn.metrics import accuracy_score # evaluation metric
from sklearn.metrics import f1_score # evaluation metric


df = pd.read_csv("creditcard.csv")
print(df.head())

df.describe()


df.drop('Time', axis = 1, inplace = True)
df.head()

df.describe()


#Data Processing and EDA
#Let’s have a look at how many fraud cases and non-fraud cases are there in our dataset. Along with that, let’s also compute the #percentage of fraud cases in the overall recorded transactions.

cases = len(df)
nonfraud_count = len(df[df.Class == 0])
fraud_count = len(df[df.Class == 1])
fraud_percentage = round(fraud_count/nonfraud_count*100, 2)

print('CASE COUNT')
print('Total number of cases are {}'.format(cases))
print('Number of Non-fraud cases are {}'.format(nonfraud_count))
print('Number of Non-fraud cases are {}'.format(fraud_count))
print('Percentage of fraud cases is {}'.format(fraud_percentage))


nonfraud_cases = df[df.Class == 0]
fraud_cases = df[df.Class == 1]

print('CASE     AMOUNT      STATISTICS')
print("---------------------------------------")
print('NON-FRAUD CASE AMOUNT STATS')
print(nonfraud_cases.Amount.describe())
print('FRAUD CASE AMOUNT STATS')
print(fraud_cases.Amount.describe())


sc = StandardScaler()
amount = df['Amount'].values

df['Amount'] = sc.fit_transform(amount.reshape(-1, 1))

print(df['Amount'].head(10))


#Feature Selection & Data Split
#In this process, we are going to define the independent (X) and the dependent variables (Y). Using the defined variables, we #will split the data into a training set and testing set which is further used for modeling and evaluating. We can split the #data easily using the 'train_test_split()'.

X = df.drop('Class', axis = 1).values
y = df['Class'].values

X_train, X_test, y_train, y_test = train_test_split(X, y, test_size = 0.2, random_state = 0)

print('X_train samples : ', X_train[:1])
print('X_test samples : ', X_test[0:1])
print('y_train samples : ', y_train[0:20])
print('y_test samples : ',  y_test[0:20])


Modeling
By using Scikit-learn package, we will be build following classification models

  1. Decision Tree,
  2. K-Nearest Neighbors (KNN),
  3. Logistic Regression,
  4. Support Vector Machine (SVM),
  5. Random Forest,
    XGBoost can also be used but we can’t use it with SKLearn packages, we need to use XGBoost package saperately.
# MODELING

# 1. Decision Tree

tree_model = DecisionTreeClassifier(max_depth = 4, criterion = 'entropy')
tree_model.fit(X_train, y_train)
tree_yhat = tree_model.predict(X_test)

# 2. K-Nearest Neighbors

n = 5

knn = KNeighborsClassifier(n_neighbors = n)
knn.fit(X_train, y_train)
knn_yhat = knn.predict(X_test)

# 3. Logistic Regression

lr = LogisticRegression()
lr.fit(X_train, y_train)
lr_yhat = lr.predict(X_test)

# 4. SVM 

svm = SVC()
svm.fit(X_train, y_train)
svm_yhat = svm.predict(X_test)

# 5. Random Forest Tree

rf = RandomForestClassifier(max_depth = 4)
rf.fit(X_train, y_train)
rf_yhat = rf.predict(X_test)

Evaluation

now we will evaluate our models using the evaluation metrics provided by the scikit-learn package to find best models. we will use following evaluation

  1. accuracy score metric,
  2. f1 score metric, and
  3. confusion matrix.

1. Accuracy score

Accuracy score = No.of correct predictions / Total no.of predictions

# 1. Accuracy score

print('ACCURACY SCORE')
print('Accuracy score of the Decision Tree model is {}'.format(accuracy_score(y_test, tree_yhat)))
print('Accuracy score of the KNN model is {}'.format(accuracy_score(y_test, knn_yhat)))
print('Accuracy score of the Logistic Regression model is {}'.format(accuracy_score(y_test, lr_yhat)))
print('Accuracy score of the SVM model is {}'.format(accuracy_score(y_test, svm_yhat)))
print('Accuracy score of the Random Forest Tree model is {}'.format(accuracy_score(y_test, rf_yhat)))

2. F1 Score

F1 score = 2( (precision * recall) / (precision + recall) )

# 2. F1 score

print('F1 SCORE')
print(cl('F1 score of the Decision Tree model is {}'.format(f1_score(y_test, tree_yhat)))
print(cl('F1 score of the KNN model is {}'.format(f1_score(y_test, knn_yhat)))
print(cl('F1 score of the Logistic Regression model is {}'.format(f1_score(y_test, lr_yhat)))
print(cl('F1 score of the SVM model is {}'.format(f1_score(y_test, svm_yhat)))
print(cl('F1 score of the Random Forest Tree model is {}'.format(f1_score(y_test, rf_yhat)))

Leave a Comment

Your email address will not be published. Required fields are marked *