README.md

---
license: mit
base_model: microsoft/deberta-v3-xsmall
library_name: transformers
pipeline_tag: text-classification
tags:
- trained-from-scratch
- deberta
- sequence-classification
- multiple-choice
- question-answering
metrics:
- map@3
- accuracy
- f1
---

# QSolver_Scratch

QSolver_Scratch is a lightweight, custom transformer model trained **completely from scratch** (random weight initialization via `.from_config()`) using a modified DeBERTa-v3 architecture. 

It uses a question-option explosion technique that reformulates 5-choice multiple-choice questions into binary sequence classification tasks (`Question: {q}\nOption: {opt_val}`). Predictions across option pairs are grouped into 5-way logit arrays to evaluate choices using Mean Average Precision at 3 (MAP@3), Accuracy, Precision, Recall, and F1-score across 5-Fold Cross-Validation.

---

## Model Details

- **Model Name:** QSolver_Scratch
- **Repository ID:** `dahaludba/QSolver_Scratch`
- **Tokenizer:** `microsoft/deberta-v3-xsmall`
- **Training Strategy:** Trained from scratch (random initial weights, no pre-trained weights used)
- **Architecture Base:** DeBERTa-v3 (Custom Reduced Variant)
- **Task Type:** Binary Sequence Classification for Multiple-Choice Ranking
- **Maximum Sequence Length:** 256 tokens
- **Total Training Duration:** 1 hour 15 minutes
- **License:** MIT License

---

## Custom Architecture Specifications

To build a lightweight, fast-executing encoder model, the base `microsoft/deberta-v3-xsmall` architecture configuration was customized with reduced layer count and embedding dimensions:

- **Number of Hidden Layers (`num_hidden_layers`):** 4 (reduced from standard 12)
- **Hidden Layer Dimension (`hidden_size`):** 256
- **Attention Heads (`num_attention_heads`):** 4
- **Feed-Forward Intermediate Dimension (`intermediate_size`):** 1024
- **Pooler Hidden Dimension (`pooler_hidden_size`):** 256
- **Number of Output Labels (`num_labels`):** 1 (binary classification logit per prompt-option pair)

---

## Data Pipeline & Exploded Formatter

Each multiple-choice sample containing a prompt and 5 candidate choices (A, B, C, D, E) is exploded into 5 independent text instances:

```text
Text:  "Question: {question_text}\nOption: {option_value}"
Label: 1.0 (if option is correct) | 0.0 (if option is incorrect)
```

During evaluation, outputs are reshaped into batches of size $(N, 5)$ where $N$ is the number of question groups. Logits are sorted in descending order to derive the top-3 predicted option ranks.

---

## Hyperparameters

| Hyperparameter | Value |
| :--- | :--- |
| Initialization Method | Random Weights (`AutoModelForSequenceClassification.from_config`) |
| Learning Rate | 1e-4 |
| LR Scheduler | Cosine Decay |
| Warmup Steps | 100 |
| Weight Decay | 0.01 |
| Per Device Train Batch Size | 64 |
| Per Device Eval Batch Size | 64 |
| Gradient Accumulation Steps | 1 |
| Epochs per Fold | 5 |
| Precision | Mixed Precision FP16 (`fp16=True`) |
| Primary Metric for Best Model | `eval_map@3` (`greater_is_better=True`) |
| Seed | 42 |

---

## Experiment Tracking & Cross-Validation Results

Training across all 5 folds completed in **1 hour and 15 minutes**. Individual run telemetry and evaluation metrics are recorded on Weights & Biases:

- **Fold 1:** [W&B Run zb6ldwgg](https://wandb.ai/24f2002963-dl-genai-project/24f2002963-t22026/runs/zb6ldwgg?nw=nwuser24f2002963)
- **Fold 2:** [W&B Run i6sht758](https://wandb.ai/24f2002963-dl-genai-project/24f2002963-t22026/runs/i6sht758?nw=nwuser24f2002963)
- **Fold 3:** [W&B Run d6zqwe0x](https://wandb.ai/24f2002963-dl-genai-project/24f2002963-t22026/runs/d6zqwe0x?nw=nwuser24f2002963)
- **Fold 4:** [W&B Run az2xrt2a](https://wandb.ai/24f2002963-dl-genai-project/24f2002963-t22026/runs/az2xrt2a?nw=nwuser24f2002963)
- **Fold 5:** [W&B Run hkzxclzi](https://wandb.ai/24f2002963-dl-genai-project/24f2002963-t22026/runs/hkzxclzi?nw=nwuser24f2002963)

---

## How to Load and Run Inference

Below is a Python snippet showing how to load a fold checkpoint and perform multi-choice scoring:

```python
import torch
import numpy as np
from transformers import AutoTokenizer, AutoModelForSequenceClassification

REPO_ID = "dahaludba/QSolver_Scratch"
SUBFOLDER = "fold_1"
TOKENIZER_NAME = "microsoft/deberta-v3-xsmall"

# Load Tokenizer and Fold Model
tokenizer = AutoTokenizer.from_pretrained(TOKENIZER_NAME)
model = AutoModelForSequenceClassification.from_pretrained(REPO_ID, subfolder=SUBFOLDER)
model.eval()

question = "What organelle is known as the powerhouse of the cell?"
options = [
    "Nucleus",
    "Mitochondria",
    "Ribosome",
    "Golgi Apparatus",
    "Endoplasmic Reticulum"
]

# Format exploded inputs
input_texts = [f"Question: {question}\nOption: {opt}" for opt in options]

# Tokenize inputs
inputs = tokenizer(
    input_texts,
    padding=True,
    truncation=True,
    max_length=256,
    return_tensors="pt"
)

with torch.no_grad():
    outputs = model(**inputs)
    logits = outputs.logits.squeeze(-1).cpu().numpy()

# Rank option choices by predicted score
option_letters = ["A", "B", "C", "D", "E"]
top3_indices = np.argsort(-logits)[:3]
top3_predictions = [f"{option_letters[idx]} ({options[idx]})" for idx in top3_indices]

print("Top-3 Predicted Options:", top3_predictions)
```

---

## License

This project and all associated model weights are released under the **MIT License**.