Untitled

import pandas as pd
import numpy as np
from sklearn.preprocessing import StandardScaler
from sklearn.decomposition import PCA
from sklearn.cluster import KMeans
from sklearn.ensemble import IsolationForest
from sklearn.model_selection import train_test_split

# Load data and preprocess
data = pd.read_csv('credit_card_transactions.csv')
data = data.drop_duplicates()
data = data.dropna()
data['datetime'] = pd.to_datetime(data['datetime'])
data['hour'] = data['datetime'].dt.hour
data = data.drop(['datetime'], axis=1)
X = data.drop(['fraudulent'], axis=1)
y = data['fraudulent']

# Feature engineering
X['amount_log'] = np.log(X['amount']+1)
X['hour_sin'] = np.sin(2*np.pi*X['hour']/24)
X['hour_cos'] = np.cos(2*np.pi*X['hour']/24)
X = X.drop(['hour'], axis=1)

# Standardize features
scaler = StandardScaler()
X_scaled = scaler.fit_transform(X)

# Reduce dimensionality using PCA
pca = PCA(n_components=10)
X_pca = pca.fit_transform(X_scaled)

# Cluster data using K-means
kmeans = KMeans(n_clusters=4, random_state=0).fit(X_pca)
X_cluster = kmeans.predict(X_pca)

# Train isolation forest model
X_train, X_test, y_train, y_test = train_test_split(X_scaled, y, test_size=0.2)
model = IsolationForest(n_estimators=100, max_samples='auto', contamination='auto')
model.fit(X_train)

# Evaluate model performance
y_pred = model.predict(X_test)
accuracy = np.mean(y_pred == y_test)
print('Accuracy:', accuracy)