RESEARCH SHOWCASE · DEPT OF INFORMATION TECHNOLOGY

Solving Majority-Class Collapse in Tanglish Sentiment AI

Standard NLP models mislabel 75% of mixed-feeling comments as positive because 70% of YouTube comments are praise. ConG-MoE v2 stops this collapse using sub-word features and discourse-guided specialist heads—at 0.33 ms on an ordinary CPU.

0Analyzed Tanglish comments
0Mixed Recall (vs 20.55% baseline)
0Mixed→Positive Collapse (vs 75.0% baseline)
0Single-core CPU latency (15.5s training)

⚡ Try ConG-MoE v2 Live

Type any Tamil-English comment or click a sample chip below to inspect real-time classification and specialist head routing.

Live Sentiment Analyzer ● Connecting Engine...
Try samples:
⚖️ MIXED FEELINGS
Latency: 0.328 ms Confidence: 74.5% Base Guess: Mixed
Specialist Decision: Contrastive pivot ('aana'/'but') connecting positive and negative clauses
Class Probability Distribution

Why Tanglish Breaks Standard NLP

70% of movie comments are positive. Naive classifiers optimize for majority accuracy, burying genuine criticism. Four linguistic bottlenecks worsen this:

1Spelling Variation

No standard Tanglish orthography: padam appears as padham, paadam, or batham. Tokenizers treat each as a new word, creating extreme sparsity.

2Agglutinative Suffixes

Suffixes (-la, -oda, -ku) stick to English roots (trailer-la, hero-oda). 85.8% of words in social feeds are Out-of-Vocabulary in transliteration dictionaries.

3Emoji Sarcasm

Cleaning scripts discard non-ASCII emojis, yet they carry the emotion: “padam mass 🤮” is sarcastic, but stripped of emojis it looks like glowing praise.

4Mid-Sentence Reversals

“Sema hype aana climax mokka”: Bag-of-words ignores clause turns, so the positive words overpower the negative clause following aana (but).

How ConG-MoE v2 Works

ConG-MoE v2 replaces resource-heavy transformers with a fast, discourse-guided 3-head mixture of experts:

Head 1 · Statistical Classifier

Class-weighted logistic regression over 35,000 sub-word n-grams (10k words + 25k word-bounded chars). Penalizes minority errors by up to 12.5×.

Head 2 · Conjunction Pivot Monitor

Watches polarity changes across pivot conjunctions (aana, aanal, irundhalum, but). Opposing sentiments on either side vote Mixed.

Head 3 · Affective Emoji Resolver

Catches emotional dissonance between text praise and disgusted emojis (e.g., praise alongside 🤮 or 👎).

Benchmark Results

Tested on 5,000 held-out Tanglish comments. ConG-MoE v2 preserves minority recall at sub-millisecond CPU speeds.

Each dot is one of 584 true Mixed comments in the test set. The baseline dumps 438 of them into Positive; ConG-MoE v2 moves them into the correct Mixed bin.

Compare Architectures on Held-Out Test Set (N = 5,000):

Table II. Held-out test evaluation. ConG-MoE v2 cuts collapse from 75.0% to 14.04% at 0.33 ms CPU latency.

Error Diagnostics & Confusion Matrix:

Qualitative Case Studies

See how ConG-MoE v2 avoids the majority-class trap on real comments:

The Research Team

KS
PROJECT MENTOR

Dr. Kannimuthu S

Professor & Research Guide, Department of Computer Science and Engineering.

Department of Information Technology, Karpagam College of Engineering, Coimbatore, Tamil Nadu, India.

📚 View Academic Citations & Direct Paper Links (14 References)
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