DeAR-3B-Reranker-RankNet-v1

Model Description

DeAR-3B-Reranker-RankNet-v1 is a 3B parameter efficient neural reranker trained with RankNet loss and knowledge distillation. This model offers the best speed-performance tradeoff in the DeAR family, achieving competitive results with significantly faster inference than larger models.

Model Details

• Model Type: Pointwise Reranker (Sequence Classification)
• Base Model: LLaMA-3.2-3B
• Parameters: 3 billion
• Training Method: Knowledge Distillation + RankNet Loss
• Teacher Model: LLaMA2-13B-RankLLaMA
• Training Data: MS MARCO + DeAR-COT
• Precision: BFloat16

Key Features

✅ Ultra Fast: 1.5s inference (1.5x faster than 8B models)
✅ Efficient: Runs on single 16GB GPU
✅ Strong Performance: Competitive with larger models
✅ Low Latency: Ideal for production deployments
✅ Small Footprint: Only 6GB model size

Speed-Performance Tradeoff: 95% accuracy at 1.5x speed!

Usage

Quick Start

import torch
from transformers import AutoTokenizer, AutoModelForSequenceClassification

# Load model
model_path = "abdoelsayed/dear-3b-reranker-ranknet-v1"
tokenizer = AutoTokenizer.from_pretrained(model_path)
model = AutoModelForSequenceClassification.from_pretrained(
    model_path,
    torch_dtype=torch.bfloat16
)
model.eval().cuda()

# Score a query-document pair
query = "What is machine learning?"
document = "Machine learning is a subset of artificial intelligence..."

inputs = tokenizer(
    f"query: {query}",
    f"document: {document}",
    return_tensors="pt",
    truncation=True,
    max_length=228,
    padding="max_length"
)
inputs = {k: v.cuda() for k, v in inputs.items()}

with torch.no_grad():
    score = model(**inputs).logits.squeeze().item()
    
print(f"Relevance score: {score}")

Batch Reranking

from typing import List, Tuple

@torch.inference_mode()
def rerank(tokenizer, model, query: str, docs: List[Tuple[str, str]], batch_size: int = 64):
    """
    Rerank documents for a query.
    
    Args:
        docs: List of (title, text) tuples
    
    Returns:
        List of (index, score) sorted by relevance
    """
    device = next(model.parameters()).device
    scores = []
    
    for i in range(0, len(docs), batch_size):
        batch = docs[i:i + batch_size]
        queries = [f"query: {query}"] * len(batch)
        documents = [f"document: {title} {text}" for title, text in batch]
        
        inputs = tokenizer(
            queries,
            documents,
            return_tensors="pt",
            truncation=True,
            max_length=228,
            padding=True
        )
        inputs = {k: v.to(device) for k, v in inputs.items()}
        
        logits = model(**inputs).logits.squeeze(-1)
        scores.extend(logits.cpu().tolist())
    
    return sorted(enumerate(scores), key=lambda x: x[1], reverse=True)


# Example
query = "When did Thomas Edison invent the light bulb?"
docs = [
    ("", "Lightning strike at Seoul National University"),
    ("", "Thomas Edison tried to invent a device for car but failed"),
    ("", "Coffee is good for diet"),
    ("", "KEPCO fixes light problems"),
    ("", "Thomas Edison invented the light bulb in 1879"),
]

ranking = rerank(tokenizer, model, query, docs)
print(ranking)
# DeAR-P-3B-RL Output:
# [(4, -1.3046875), (1, -5.125), (3, -6.3125), (0, -6.4375), (2, -6.96875)]

Training Details

Training Configuration

{
    "base_model": "meta-llama/Llama-3.2-3B",
    "teacher_model": "abdoelsayed/llama2-13b-rankllama-teacher",
    "loss": "RankNet",
    "distillation": {
        "temperature": 2.0,
        "alpha": 0.1
    },
    "learning_rate": 1e-4,
    "batch_size": 4,
    "gradient_accumulation": 2,
    "epochs": 2,
    "max_length": 228,
    "bf16": true
}

Hardware

• GPUs: 4x NVIDIA A100 (40GB)
• Training Time: ~18 hours (2x faster than 8B)
• Memory Usage: ~24GB per GPU
• Framework: DeepSpeed ZeRO Stage 2

Loss Function

RankNet Loss with Knowledge Distillation:

L_total = (1 - α) * L_RankNet + α * L_KD
where α = 0.1, temperature = 2.0

Evaluation Results

TREC Deep Learning

Dataset	NDCG@10	NDCG@20	MRR@10	MAP
DL19	71.2	67.8	84.5	42.1
DL20	69.4	66.2	82.3	40.5

BEIR Benchmark

Dataset	NDCG@10
MS MARCO	65.8
NQ	49.2
HotpotQA	58.4
FiQA	44.1
ArguAna	56.2
SciFact	70.8
TREC-COVID	82.3
NFCorpus	37.6
Average	42.1

Efficiency Metrics

Metric	Value
Inference Time (100 docs)	1.5s
Throughput	~67 docs/sec
GPU Memory (inference)	12GB
Model Size (BF16)	6GB

Comparison

vs. Larger Models

Model	Size	DL19	DL20	BEIR	Speed (s)
DeAR-3B-RL	3B	71.2	69.4	42.1	1.5
DeAR-8B-RL	8B	74.5	72.8	45.2	2.2
Teacher-13B	13B	73.8	71.2	44.8	5.8
MonoT5-3B	3B	71.8	68.9	43.5	3.5

Key Insight: Similar accuracy to MonoT5-3B with 2.3x faster inference!

Speed-Accuracy Tradeoff

Accuracy: 95% of 8B model performance
Speed: 1.5x faster
Memory: 50% less GPU memory
Size: 38% smaller on disk

Model Architecture

Input: "query: [Q] [SEP] document: [D]"
    ↓
LLaMA-3.2-3B Encoder (24 layers)
    ↓
[CLS] Token Representation
    ↓
Linear Classification Head
    ↓
Relevance Score

When to Use This Model

Best for:

• ✅ Production deployments requiring low latency
• ✅ Resource-constrained environments
• ✅ Large-scale reranking (millions of queries)
• ✅ Cost-sensitive applications
• ✅ Single GPU inference

Consider 8B models for:

• ❌ Maximum accuracy required
• ❌ Research benchmarks
• ❌ GPU resources not a constraint

Deployment Recommendations

Production Setup

# Optimize for inference
model = AutoModelForSequenceClassification.from_pretrained(
    "abdoelsayed/dear-3b-reranker-ranknet-v1",
    torch_dtype=torch.bfloat16,
    device_map="auto"
)
model.eval()

# Enable torch.compile for 20% speedup (PyTorch 2.0+)
model = torch.compile(model, mode="reduce-overhead")

Batch Processing

For maximum throughput:

• Use batch size 64-128
• Enable mixed precision (bf16)
• Use torch.compile()
• Consider ONNX export for CPU deployment

Limitations

1. Accuracy: ~3 NDCG@10 points lower than 8B models
2. Complex Queries: May struggle with nuanced queries
3. Document Length: Same 196 token limit as larger models
4. Language: English only

Fine-tuning

from transformers import AutoModelForSequenceClassification, TrainingArguments, Trainer

model = AutoModelForSequenceClassification.from_pretrained(
    "abdoelsayed/dear-3b-reranker-ranknet-v1"
)

training_args = TrainingArguments(
    output_dir="./finetuned-3b",
    learning_rate=5e-6,  # Lower for fine-tuning
    per_device_train_batch_size=8,
    num_train_epochs=2,
    bf16=True,
)

trainer = Trainer(
    model=model,
    args=training_args,
    train_dataset=your_dataset,
)

trainer.train()

Related Models

DeAR 3B Family:

• DeAR-3B-CE - Binary Cross-Entropy variant
• DeAR-3B-RankNet-LoRA - LoRA adapter

Larger Models:

• DeAR-8B-RankNet - Better accuracy

Resources:

• Teacher Model
• DeAR-COT Dataset

Citation

@article{abdallah2025dear,
  title={DeAR: Dual-Stage Document Reranking with Reasoning Agents via LLM Distillation},
  author={Abdallah, Abdelrahman and Mozafari, Jamshid and Piryani, Bhawna and Jatowt, Adam},
  journal={arXiv preprint arXiv:2508.16998},
  year={2025}
}

License

MIT License

More Information

• GitHub: DataScienceUIBK/DeAR-Reranking
• Paper: arXiv:2508.16998
• Collection: DeAR Models