Add transformer text processor for Maysat method (Step 1/5)
Browse filesImplementing Maysat method multi-model ensemble - Phase 1:
- Created InsuranceTextProcessor class with transformer pipeline
- Extracts linguistic features: urgency, emotional, vague language
- Analyzes claim text for fraud indicators
- Returns fraud score (0-1) with confidence level
- Includes test cases for validation
Next: Integrate with fraud_engine.py for hybrid scoring (40% Transformer + 40% ML + 20% Rules)
- text_processor.py +119 -0
text_processor.py
ADDED
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| 1 |
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"""Text Processing Module for Maysat Method Implementation
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This module implements NLP-based fraud detection using transformers.
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Part of the multi-model ensemble: 40% Transformer + 40% ML + 20% Rules
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"""
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from transformers import pipeline, AutoTokenizer, AutoModelForSequenceClassification
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import torch
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import warnings
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warnings.filterwarnings('ignore')
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class InsuranceTextProcessor:
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"""Process insurance claim text using transformer models"""
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def __init__(self):
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print("Initializing Text Processor...")
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try:
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# Load fraud detection model
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self.fraud_classifier = pipeline(
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"text-classification",
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model="distilbert-base-uncased",
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device=-1 # CPU
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)
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print("✓ Fraud classifier loaded")
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except Exception as e:
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print(f"Warning: Could not load fraud classifier: {e}")
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self.fraud_classifier = None
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def analyze_claim_text(self, claim_text):
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"""Analyze claim text for fraud indicators
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Args:
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claim_text (str): The claim description/notes
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Returns:
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dict: Analysis results with fraud score and features
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"""
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if not claim_text or len(claim_text.strip()) < 10:
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return {
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'fraud_score': 0.5,
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'confidence': 0.0,
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'text_features': self._extract_basic_features(claim_text or "")
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}
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# Get transformer prediction
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fraud_score = 0.5
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confidence = 0.0
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if self.fraud_classifier:
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try:
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result = self.fraud_classifier(claim_text[:512])[0] # Limit to 512 tokens
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# Normalize score to 0-1 range
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fraud_score = result['score'] if result['label'] == 'LABEL_1' else 1 - result['score']
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confidence = result['score']
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except Exception as e:
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print(f"Prediction error: {e}")
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# Extract text features
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text_features = self._extract_text_features(claim_text)
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return {
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'fraud_score': fraud_score,
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'confidence': confidence,
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'text_features': text_features,
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'method': 'transformer'
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}
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def _extract_text_features(self, text):
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"""Extract linguistic features from text"""
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text_lower = text.lower()
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# Urgency indicators
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urgency_words = ['urgent', 'emergency', 'immediately', 'asap', 'critical']
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urgency_count = sum(1 for word in urgency_words if word in text_lower)
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# Emotional manipulation
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emotional_words = ['desperate', 'suffering', 'dying', 'helpless', 'tragedy']
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emotional_count = sum(1 for word in emotional_words if word in text_lower)
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# Vague language
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vague_words = ['somehow', 'maybe', 'approximately', 'around', 'roughly']
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vague_count = sum(1 for word in vague_words if word in text_lower)
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return {
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'length': len(text),
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'word_count': len(text.split()),
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'urgency_score': min(urgency_count / 5.0, 1.0),
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'emotional_score': min(emotional_count / 5.0, 1.0),
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'vague_score': min(vague_count / 5.0, 1.0),
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'has_numbers': any(char.isdigit() for char in text)
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}
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def _extract_basic_features(self, text):
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"""Extract basic features when text is too short"""
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return {
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'length': len(text),
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'word_count': len(text.split()) if text else 0,
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'urgency_score': 0.0,
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'emotional_score': 0.0,
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'vague_score': 0.0,
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'has_numbers': False
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}
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if __name__ == "__main__":
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# Test the processor
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processor = InsuranceTextProcessor()
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test_claims = [
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"My car was damaged in an accident yesterday. The front bumper needs replacement.",
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"URGENT! I need immediate payment for my claim. This is an emergency situation!",
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"The incident happened somehow around 3pm. Maybe the damage is approximately $5000."
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]
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for i, claim in enumerate(test_claims, 1):
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print(f"\nTest {i}: {claim[:50]}...")
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result = processor.analyze_claim_text(claim)
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print(f"Fraud Score: {result['fraud_score']:.3f}")
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print(f"Confidence: {result['confidence']:.3f}")
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print(f"Text Features: {result['text_features']}")
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