Model Description
Qwen-NER-Decoder is a fine-tuned decoder-only Named Entity Recognition (NER) model based on Qwen/Qwen2.5-0.5B-Instruct.
The model identifies and extracts named entities from English text and generates structured JSON output.
It is fine-tuned on the CoNLL-2003 English Named Entity Recognition dataset and recognizes four entity categories:
- PER – Person
- ORG – Organization
- LOC – Location
- MISC – Miscellaneous
The model uses Low-Rank Adaptation (LoRA) for parameter-efficient fine-tuning. The Hugging Face repository contains the LoRA adapter, so it must be loaded together with its original base model.
Model Details
Table with columns: Property, Details| Property | Details |
|---|
| Model Name | Qwen-NER-Decoder |
| Base Model | Qwen/Qwen2.5-0.5B-Instruct |
| Architecture | Decoder-only Transformer |
| Fine-tuning Method | LoRA |
| LoRA Rank | 8 |
| LoRA Alpha | 16 |
| LoRA Dropout | 0.05 |
| Training Epochs | 1 |
| Language | English |
| Task | Named Entity Recognition |
| Output Format | JSON |
| Training Framework | PyTorch, Transformers, PEFT |
Dataset
The model was fine-tuned using the CoNLL-2003 English NER dataset.
Dataset repository: lhoestq/conll2003
The dataset contains English sentences annotated with BIO-style named entity labels.
The four entity categories are:
Table with columns: Label, Description| Label | Description |
|---|
| PER | Person |
| ORG | Organization |
| LOC | Location |
| MISC | Miscellaneous |
Training Configuration
The model was fine-tuned using LoRA with the following configuration:
Table with columns: Configuration, Value| Configuration | Value |
|---|
| Base Model | Qwen2.5-0.5B-Instruct |
| LoRA Rank | 8 |
| LoRA Alpha | 16 |
| LoRA Dropout | 0.05 |
| Target Modules | q_proj, k_proj, v_proj, o_proj |
| Training Epochs | 1 |
| Training Samples | Up to 8,000 |
| Validation Samples | 1,000 |
| Training Precision | FP16 |
| Optimizer | AdamW |
| Training Environment | Kaggle GPU |
LoRA adapts selected attention projection layers without updating all the parameters of the original base model.
Evaluation Results
The model was evaluated on a quick test subset of 100 English sentences using exact entity-level matching.
Table with columns: Metric, Score| Metric | Score |
|---|
| Precision | 90.40% |
| Recall | 81.63% |
| F1-score | 85.79% |
| True Positives | 160 |
| False Positives | 17 |
| False Negatives | 36 |
Evaluation note: These results represent the 100-sample evaluation subset, not the complete test dataset. They should not be interpreted as a full-dataset benchmark.
Additional manually selected English sentences were used to inspect entity extraction behavior.
Example Predictions
Example 1
Input:
Elon Musk founded SpaceX.
Output:
{ "entities": [ { "text": "Elon Musk", "type": "PER" }, { "text": "SpaceX", "type": "ORG" } ]}
Example 2
Input:
Barack Obama visited Microsoft headquarters in Seattle.
Output:
{ "entities": [ { "text": "Barack Obama", "type": "PER" }, { "text": "Microsoft", "type": "ORG" }, { "text": "Seattle", "type": "LOC" } ]}
Examples illustrate the intended output structure.
How to Use
1. Install Dependencies
pip install torch transformers peft accelerate safetensors
2. Load the Base Model and LoRA Adapter
import torchfrom transformers import AutoTokenizer, AutoModelForCausalLMfrom peft import PeftConfig, PeftModel ADAPTER_MODEL = "ullahhafeez321/Qwen-NER-Decoder" # Read the original base model from the adapter configurationadapter_config = PeftConfig.from_pretrained(ADAPTER_MODEL)BASE_MODEL = adapter_config.base_model_name_or_path # Load tokenizer from the base modeltokenizer = AutoTokenizer.from_pretrained(BASE_MODEL) if tokenizer.pad_token_id is None: tokenizer.pad_token = tokenizer.eos_token # Load the original Qwen base modelbase_model = AutoModelForCausalLM.from_pretrained( BASE_MODEL, torch_dtype=( torch.float16 if torch.cuda.is_available() else torch.float32 ), device_map="auto") # Attach the fine-tuned LoRA adaptermodel = PeftModel.from_pretrained( base_model, ADAPTER_MODEL) model.eval() print("Qwen NER model loaded successfully!")
3. Run Inference
The prompt used during inference should follow the same instruction and output format used during fine-tuning.
The following is an illustrative JSON extraction example:
sentence = "Albert Einstein worked at Princeton University." prompt = f"""Extract named entities from the following sentence. Entity types:PER = PersonORG = OrganizationLOC = LocationMISC = Miscellaneous Return only a JSON array: [ {{"text": "entity name", "type": "PER"}}] If no entities are found, return []. Sentence: {sentence} Entities:""" inputs = tokenizer( prompt, return_tensors="pt", truncation=True, max_length=1024) input_device = model.get_input_embeddings().weight.deviceinputs = { key: value.to(input_device) for key, value in inputs.items()} with torch.inference_mode(): outputs = model.generate( **inputs, max_new_tokens=150, do_sample=False, pad_token_id=tokenizer.pad_token_id, eos_token_id=tokenizer.eos_token_id ) generated_tokens = outputs[0][inputs["input_ids"].shape[1]:] result = tokenizer.decode( generated_tokens, skip_special_tokens=True) print(result)
Note: This example demonstrates the inference process. For the best results, use the exact prompt template and target format used to train the uploaded adapter.
Intended Use
This model is intended for:
- English named entity recognition.
- Natural Language Processing applications.
- Information extraction systems.
- Text analysis and document processing.
- Educational and research projects.
- Integration with sentiment classification systems.
- Applications that require structured entity extraction.
Limitations
- The model may occasionally miss named entities.
- Some entities may receive incorrect classifications.
- Entity boundaries and spelling may occasionally be incorrect.
- Performance can vary across different domains and writing styles.
- The reported evaluation score is based on a limited 100-sample test subset.
- The model is intended for English text and may not perform reliably on other languages.
- The model is not intended to replace human verification in critical applications.
Model Architecture
This project uses a decoder-only Transformer architecture based on Qwen2.5-0.5B-Instruct.
The model generates structured entity extraction results from an English input sentence.
LoRA fine-tuning adapts selected attention projection layers while preserving the original base model weights.
The uploaded Hugging Face repository contains the fine-tuned adapter rather than a complete standalone model checkpoint.
Future Improvements
- Increase training data and training epochs.
- Improve recall and entity coverage.
- Evaluate performance on the complete test dataset.
- Improve entity boundary detection.
- Expand evaluation across different English text domains.
- Improve inference consistency and structured JSON generation.
- Integrate with an encoder-only BERT sentiment classification model.
Acknowledgements
License
The adapter repository declares the Apache-2.0 license. Please also review the original base model and dataset licenses and their respective usage conditions before redistribution or commercial use.
Project: English Named Entity Recognition using a Decoder-only Transformer with LoRA Fine-tuning.
Model Repository: ullahhafeez321/Qwen-NER-Decoder
Base Model: Qwen/Qwen2.5-0.5B-Instruct
Frameworks: PyTorch, Transformers, PEFT, Hugging Face Datasets.