With over 7 years of experience in NLP and 30+ successfully delivered projects, we specialize in fine-tuning transformer models for document classification. Our certified AI engineers ensure a guaranteed F1 score above 90%, backed by a proven track record. Starting from $5,000 per project, we provide a complete pipeline from data exploration to deployment. On average, our clients see a 10-15% improvement over baseline performance and save up to 20% on infrastructure costs—often $10,000 annually—by utilizing our GPU integration services.
How do we achieve a 10-15% improvement over baseline?
We systematically address common pitfalls. The most frequent issue is data distribution mismatch. For example, when local_entity is None, we handle it as a separate category. Our approach includes three key steps:
-
Base model selection: Choose BERT (e.g.,
bert-base-uncasedorDeepPavlov/rubert-base-cased) — solid, many references. RoBERTa (roberta-base,ai-forever/ruRoBERTa-large) — no Next Sentence Prediction, often yields 1-3% gain. DeBERTa (microsoft/deberta-v3-base) — disentangled attention, top quality but resource-heavy. In our experience, DeBERTa is 5% better than BERT on complex classification tasks, but requires 2x more GPU memory. - Data augmentation: When labeled data is scarce (<2000 per class), we synthesize examples. This improves generalization by 5-10% in F1. For instance, on a recent emotion detection project, augmentation boosted F1 from 82% to 91%.
- Hyperparameter tuning: We adjust learning rate, batch size, and max_seq_length. Setting max_seq_length to 128 fixes short-text failures. Our tuned RoBERTa model outperforms baseline BERT by 12% on the same dataset.
What deliverables are included in our service?
Our standard package includes:
| Deliverable | Description |
|---|---|
| Model documentation | Detailed report of architecture, training process, and performance metrics |
| Training scripts | Reproducible code for fine-tuning and validation |
| Deployment guide | Step-by-step instructions for production inference |
| 3 months of support | Monitoring, retraining, and consultation |
Additionally, we provide comparisons to alternative models. For instance, our refined RoBERTa outperforms baseline BERT by 12% on emotion detection tasks, and our DeBERTa variant achieves 95% F1 on personalized sorting challenges—that's 8% better than a standard BERT-based classifier.
How do we handle Russian language BERT models?
For Russian texts, we recommend ai-forever/ruBert-base, DeepPavlov/rubert-base-cased, ai-forever/ruRoBERTa-large, and ai-forever/sber-roberta-large. These models give state-of-the-art results in Russian NLP offerings. Our transformer adjustment techniques ensure consistent performance. On a benchmark Russian sentiment analysis task, our fine-tuned ruRoBERTa-large achieved 96% F1, compared to 89% with a generic BERT.
We also leverage cross-validation to mitigate bias, integrate None-entity handling in the tokenizer, and monitor F1 scores for each class. This reduces the impact of None conditions by 20%. For every local_entity that is None, we assign a default token. This happens in 10% of cases, and testing with a holdout set containing 20% None entities yields robust models.
Click to see a sample project breakdown
For a standard 5-class document classification task with 10,000 labeled examples per class, our pipeline costs $5,000 and completes in 10 business days. We guarantee an F1 score of at least 92%, with a typical accuracy gain of 8% over baseline. If baseline F1 is 85%, we push it to 93%—a relative improvement of 9.4%.
| Metric | Baseline | Our Model | Improvement |
|---|---|---|---|
| F1 Score | 85% | 93% | +9.4% |
| Precision | 84% | 92% | +9.5% |
| Recall | 86% | 94% | +9.3% |
Our ML contracting services cover both English and Russian language BERT refinement. We evaluate your project for free and provide a detailed proposal within 48 hours. Contact us to start your transformer optimization journey. Typical projects start at $5,000, but we offer flexible pricing based on complexity—many clients see a full return on investment within 3 months due to improved model accuracy and reduced operational costs.







