File size: 19,536 Bytes
62a2f1c
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
import os
import numpy as np
import pandas as pd
import torch
from typing import Dict, List, Tuple, Union, Optional
import nltk
from nltk.corpus import wordnet as wn
from nltk.tokenize import word_tokenize
import re
import logging

# Configure logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# Ensure NLTK resources are available
def ensure_nltk_resources():
    """Ensure necessary NLTK resources are downloaded"""
    resources = ['punkt', 'wordnet']
    for resource in resources:
        try:
            nltk.data.find(f'tokenizers/{resource}')
            logger.info(f"NLTK resource {resource} already exists")
        except LookupError:
            try:
                logger.info(f"Downloading NLTK resource {resource}")
                nltk.download(resource, quiet=False)
                logger.info(f"NLTK resource {resource} downloaded successfully")
            except Exception as e:
                logger.error(f"Failed to download NLTK resource {resource}: {str(e)}")
    
    # Try to download punkt_tab resource
    try:
        nltk.data.find('tokenizers/punkt_tab')
    except LookupError:
        try:
            logger.info("Downloading NLTK resource punkt_tab")
            nltk.download('punkt_tab', quiet=False)
            logger.info("NLTK resource punkt_tab downloaded successfully")
        except Exception as e:
            logger.warning(f"Failed to download NLTK resource punkt_tab: {str(e)}")
            logger.info("Will use alternative tokenization method")

# Try to download resources when module is imported
ensure_nltk_resources()

# Ensure necessary NLTK resources are downloaded
try:
    nltk.data.find('tokenizers/punkt')
except LookupError:
    nltk.download('punkt')
try:
    nltk.data.find('corpora/wordnet')
except LookupError:
    nltk.download('wordnet')

# Simple tokenization function, not dependent on NLTK
def simple_tokenize(text):
    """Simple tokenization function using regular expressions"""
    if not isinstance(text, str):
        return []
    # Convert text to lowercase
    text = text.lower()
    # Use regular expressions for tokenization, preserving letters, numbers, and some basic punctuation
    import re
    tokens = re.findall(r'\b\w+\b|[!?,.]', text)
    return tokens

# Add more robust tokenization processing
def safe_tokenize(text):
    """Safe tokenization function, uses simple tokenization method when NLTK tokenization fails"""
    if not isinstance(text, str):
        return []
    
    # First try using NLTK's word_tokenize
    punkt_available = True
    try:
        nltk.data.find('tokenizers/punkt')
    except LookupError:
        punkt_available = False
    
    if punkt_available:
        try:
            return word_tokenize(text.lower())
        except Exception as e:
            logger.warning(f"NLTK tokenization failed: {str(e)}")
    
    # If NLTK tokenization is not available or fails, use simple tokenization method
    return simple_tokenize(text)

# Load psycholinguistic dictionary (simulated - should use real data in actual applications)
class PsycholinguisticFeatures:
    def __init__(self, lexicon_path: Optional[str] = None):
        """
        Initialize psycholinguistic feature extractor
        
        Args:
            lexicon_path: Path to psycholinguistic lexicon, uses simulated data if None
        """
        # If no lexicon is provided, create a simple simulated dictionary
        if lexicon_path and os.path.exists(lexicon_path):
            self.lexicon = pd.read_csv(lexicon_path)
            self.word_to_scores = {
                row['word']: {
                    'valence': row['valence'],
                    'arousal': row['arousal'],
                    'dominance': row['dominance']
                } for _, row in self.lexicon.iterrows()
            }
        else:
            # Create simulated dictionary
            self.word_to_scores = {}
            # Sentiment vocabulary
            positive_words = ['good', 'great', 'excellent', 'happy', 'joy', 'love', 'nice', 'wonderful', 'amazing', 'fantastic']
            negative_words = ['bad', 'terrible', 'awful', 'sad', 'hate', 'poor', 'horrible', 'disappointing', 'worst', 'negative']
            neutral_words = ['the', 'a', 'is', 'are', 'was', 'were', 'be', 'been', 'being', 'and', 'or', 'but', 'if', 'while', 'when']
            
            # Assign high values to positive words
            for word in positive_words:
                self.word_to_scores[word] = {
                    'valence': np.random.uniform(0.7, 0.9),
                    'arousal': np.random.uniform(0.5, 0.8),
                    'dominance': np.random.uniform(0.6, 0.9)
                }
            
            # Assign low values to negative words
            for word in negative_words:
                self.word_to_scores[word] = {
                    'valence': np.random.uniform(0.1, 0.3),
                    'arousal': np.random.uniform(0.5, 0.8),
                    'dominance': np.random.uniform(0.1, 0.4)
                }
            
            # Assign medium values to neutral words
            for word in neutral_words:
                self.word_to_scores[word] = {
                    'valence': np.random.uniform(0.4, 0.6),
                    'arousal': np.random.uniform(0.3, 0.5),
                    'dominance': np.random.uniform(0.4, 0.6)
                }
    
    def get_token_scores(self, token: str) -> Dict[str, float]:
        """Get psycholinguistic scores for a single token"""
        token = token.lower()
        if token in self.word_to_scores:
            return self.word_to_scores[token]
        else:
            # Return medium values for unknown words
            return {
                'valence': 0.5,
                'arousal': 0.5,
                'dominance': 0.5
            }
    
    def get_importance_score(self, token: str) -> float:
        """Calculate importance score for a token"""
        scores = self.get_token_scores(token)
        # Importance score is a weighted combination of valence, arousal, and dominance
        # Here we give valence a higher weight because it is more relevant to sentiment analysis
        importance = 0.6 * abs(scores['valence'] - 0.5) + 0.2 * scores['arousal'] + 0.2 * scores['dominance']
        return importance
    
    def compute_scores_for_text(self, text: str) -> List[Dict[str, float]]:
        """Calculate psycholinguistic scores for each token in the text"""
        tokens = safe_tokenize(text)
        return [self.get_token_scores(token) for token in tokens]
    
    def compute_importance_for_text(self, text: str) -> List[float]:
        """Calculate importance scores for each token in the text"""
        tokens = safe_tokenize(text)
        return [self.get_importance_score(token) for token in tokens]


class LinguisticRules:
    def __init__(self):
        """Initialize linguistic rules processor"""
        # Regular expressions for sarcasm patterns
        self.sarcasm_patterns = [
            r'(so|really|very|totally) (great|nice|good|wonderful|fantastic)',
            r'(yeah|sure|right),? (like|as if)',
            r'(oh|ah),? (great|wonderful|fantastic|perfect)'
        ]
        
        # List of negation words
        self.negation_words = [
            'not', 'no', 'never', 'none', 'nobody', 'nothing', 'neither', 'nor', 'nowhere',
            "don't", "doesn't", "didn't", "won't", "wouldn't", "couldn't", "shouldn't", "isn't", "aren't", "wasn't", "weren't"
        ]
        
        # Polysemous words and their possible substitutes
        self.polysemy_words = {
            'fine': ['good', 'acceptable', 'penalty', 'delicate'],
            'right': ['correct', 'appropriate', 'conservative', 'direction'],
            'like': ['enjoy', 'similar', 'such as', 'want'],
            'mean': ['signify', 'unkind', 'average', 'intend'],
            'kind': ['type', 'benevolent', 'sort', 'sympathetic'],
            'fair': ['just', 'pale', 'average', 'exhibition'],
            'light': ['illumination', 'lightweight', 'pale', 'ignite'],
            'hard': ['difficult', 'solid', 'harsh', 'diligent'],
            'sound': ['noise', 'healthy', 'logical', 'measure'],
            'bright': ['intelligent', 'luminous', 'vivid', 'promising']
        }
    
    def detect_sarcasm(self, text: str) -> bool:
        """Detect if sarcasm patterns exist in the text"""
        text = text.lower()
        for pattern in self.sarcasm_patterns:
            if re.search(pattern, text):
                return True
        return False
    
    def detect_negation(self, text: str) -> List[int]:
        """Detect positions of negation words in the text"""
        tokens = safe_tokenize(text)
        negation_positions = []
        for i, token in enumerate(tokens):
            if token in self.negation_words:
                negation_positions.append(i)
        return negation_positions
    
    def find_polysemy_words(self, text: str) -> Dict[int, List[str]]:
        """Find polysemous words in the text and their possible substitutes"""
        tokens = safe_tokenize(text)
        polysemy_positions = {}
        for i, token in enumerate(tokens):
            if token in self.polysemy_words:
                polysemy_positions[i] = self.polysemy_words[token]
        return polysemy_positions
    
    def get_wordnet_synonyms(self, word: str) -> List[str]:
        """Get synonyms from WordNet"""
        synonyms = []
        for syn in wn.synsets(word):
            for lemma in syn.lemmas():
                synonyms.append(lemma.name())
        return list(set(synonyms))
    
    def apply_rule_transformations(self, token_embeddings: torch.Tensor, text: str, tokenizer) -> torch.Tensor:
        """
        Apply rule-based transformations to token embeddings
        
        Args:
            token_embeddings: Original token embeddings [batch_size, seq_len, hidden_dim]
            text: Original text
            tokenizer: Tokenizer
        
        Returns:
            Transformed token embeddings
        """
        # Clone original embeddings
        transformed_embeddings = token_embeddings.clone()
        
        try:
            # Detect sarcasm
            if self.detect_sarcasm(text):
                # For sarcasm, we reverse sentiment-related embedding dimensions
                # This is a simplified implementation, more complex transformations may be needed in real applications
                sentiment_dims = torch.randperm(token_embeddings.shape[-1])[:token_embeddings.shape[-1]//10]
                transformed_embeddings[:, :, sentiment_dims] = -transformed_embeddings[:, :, sentiment_dims]
            
            # Handle negation
            negation_positions = self.detect_negation(text)
            if negation_positions:
                # For words following negation words, reverse their sentiment-related embedding dimensions
                try:
                    tokens = tokenizer.tokenize(text)
                except Exception as e:
                    logger.warning(f"Tokenization failed: {str(e)}, using alternative tokenization")
                    tokens = safe_tokenize(text)
                
                for pos in negation_positions:
                    if pos + 1 < len(tokens):  # Ensure there's a word after the negation
                        # Find the position of the token after negation in the embeddings
                        # Simplified handling, actual applications should consider tokenization differences
                        sentiment_dims = torch.randperm(token_embeddings.shape[-1])[:token_embeddings.shape[-1]//10]
                        if pos + 1 < token_embeddings.shape[1]:  # Ensure not exceeding embedding dimensions
                            transformed_embeddings[:, pos+1, sentiment_dims] = -transformed_embeddings[:, pos+1, sentiment_dims]
            
            # Handle polysemy
            polysemy_positions = self.find_polysemy_words(text)
            if polysemy_positions:
                # For polysemous words, add some noise to simulate semantic ambiguity
                for pos in polysemy_positions:
                    if pos < token_embeddings.shape[1]:  # Ensure not exceeding embedding dimensions
                        noise = torch.randn_like(transformed_embeddings[:, pos, :]) * 0.1
                        transformed_embeddings[:, pos, :] += noise
        except Exception as e:
            logger.error(f"Error applying rule transformations: {str(e)}")
            # Return original embeddings in case of error
        
        return transformed_embeddings


class HybridNoiseAugmentation:
    def __init__(
        self, 
        sigma: float = 0.1, 
        alpha: float = 0.5,
        gamma: float = 0.1,
        psycholinguistic_features: Optional[PsycholinguisticFeatures] = None,
        linguistic_rules: Optional[LinguisticRules] = None
    ):
        """
        Initialize hybrid noise augmentation
        
        Args:
            sigma: Scaling factor for Gaussian noise
            alpha: Mixing weight parameter
            gamma: Adjustment parameter in attention mechanism
            psycholinguistic_features: Psycholinguistic feature extractor
            linguistic_rules: Linguistic rules processor
        """
        self.sigma = sigma
        self.alpha = alpha
        self.gamma = gamma
        self.psycholinguistic_features = psycholinguistic_features or PsycholinguisticFeatures()
        self.linguistic_rules = linguistic_rules or LinguisticRules()
    
    def apply_psycholinguistic_noise(
        self, 
        token_embeddings: torch.Tensor, 
        texts: List[str],
        tokenizer
    ) -> torch.Tensor:
        """
        Apply psycholinguistic-based noise
        
        Args:
            token_embeddings: Original token embeddings [batch_size, seq_len, hidden_dim]
            texts: List of original texts
            tokenizer: Tokenizer
        
        Returns:
            Token embeddings with applied noise
        """
        batch_size, seq_len, hidden_dim = token_embeddings.shape
        noised_embeddings = token_embeddings.clone()
        
        for i, text in enumerate(texts):
            try:
                # Calculate importance scores for each token
                importance_scores = self.psycholinguistic_features.compute_importance_for_text(text)
                
                # Tokenize the text to match the model's tokenization
                try:
                    model_tokens = tokenizer.tokenize(text)
                except Exception as e:
                    logger.warning(f"Model tokenization failed: {str(e)}, using alternative tokenization")
                    model_tokens = safe_tokenize(text)
                
                # Assign importance scores to each token (simplified handling)
                token_scores = torch.ones(seq_len, device=token_embeddings.device) * 0.5
                for j, token in enumerate(model_tokens[:seq_len-2]):  # Exclude [CLS] and [SEP]
                    if j < len(importance_scores):
                        token_scores[j+1] = importance_scores[j]  # +1 is for [CLS]
                
                # Scale noise according to importance scores
                noise = torch.randn_like(token_embeddings[i]) * self.sigma
                scaled_noise = noise * token_scores.unsqueeze(1)
                
                # Apply noise
                noised_embeddings[i] = token_embeddings[i] + scaled_noise
            except Exception as e:
                logger.error(f"Error processing text {i}: {str(e)}")
                # Use original embeddings in case of error
                continue
        
        return noised_embeddings
    
    def apply_rule_based_perturbation(
        self, 
        token_embeddings: torch.Tensor, 
        texts: List[str],
        tokenizer
    ) -> torch.Tensor:
        """
        Apply rule-based perturbation
        
        Args:
            token_embeddings: Original token embeddings [batch_size, seq_len, hidden_dim]
            texts: List of original texts
            tokenizer: Tokenizer
        
        Returns:
            Token embeddings with applied perturbation
        """
        batch_size = token_embeddings.shape[0]
        perturbed_embeddings = token_embeddings.clone()
        
        for i, text in enumerate(texts):
            try:
                # Apply rule transformations
                perturbed_embeddings[i:i+1] = self.linguistic_rules.apply_rule_transformations(
                    token_embeddings[i:i+1], text, tokenizer
                )
            except Exception as e:
                logger.error(f"Error applying rule transformations to text {i}: {str(e)}")
                # Keep original embeddings in case of error
                continue
        
        return perturbed_embeddings
    
    def generate_hybrid_embeddings(
        self, 
        token_embeddings: torch.Tensor, 
        texts: List[str],
        tokenizer
    ) -> torch.Tensor:
        """
        Generate hybrid embeddings
        
        Args:
            token_embeddings: Original token embeddings [batch_size, seq_len, hidden_dim]
            texts: List of original texts
            tokenizer: Tokenizer
        
        Returns:
            Hybrid embeddings
        """
        # Apply psycholinguistic noise
        psycholinguistic_embeddings = self.apply_psycholinguistic_noise(token_embeddings, texts, tokenizer)
        
        # Apply rule-based perturbation
        rule_based_embeddings = self.apply_rule_based_perturbation(token_embeddings, texts, tokenizer)
        
        # Mix the two types of embeddings
        hybrid_embeddings = (
            self.alpha * psycholinguistic_embeddings + 
            (1 - self.alpha) * rule_based_embeddings
        )
        
        return hybrid_embeddings
    
    def generate_psycholinguistic_alignment_matrix(
        self, 
        texts: List[str], 
        seq_len: int,
        device: torch.device
    ) -> torch.Tensor:
        """
        Generate psycholinguistic alignment matrix
        
        Args:
            texts: List of original texts
            seq_len: Sequence length
            device: Computation device
        
        Returns:
            Psycholinguistic alignment matrix [batch_size, seq_len, seq_len]
        """
        batch_size = len(texts)
        H = torch.zeros((batch_size, seq_len, seq_len), device=device)
        
        for i, text in enumerate(texts):
            try:
                # Calculate importance scores for each token
                importance_scores = self.psycholinguistic_features.compute_importance_for_text(text)
                
                # Pad to sequence length
                padded_scores = importance_scores + [0.5] * (seq_len - len(importance_scores))
                padded_scores = padded_scores[:seq_len]
                
                # Create alignment matrix
                scores_tensor = torch.tensor(padded_scores, device=device)
                # Use outer product to create matrix, emphasizing relationships between important tokens
                H[i] = torch.outer(scores_tensor, scores_tensor)
            except Exception as e:
                logger.error(f"Error generating alignment matrix for text {i}: {str(e)}")
                # Use default values in case of error
                H[i] = torch.eye(seq_len, device=device) * 0.5
        
        return H