bactrianus/HotpotQA-Reader-CoT-Llama-3-8B-Instruct
Bactrainus HotpotQA Rationale Reader — Llama 3 8B Instruct
<p align="center"> <img src="assets/models.png" alt="Bactrainus Llama 3 model collection artwork" width="720"> </p>
Artifact identity
- Status: complete merged causal-language-model checkpoint
- Base model:
meta-llama/Meta-Llama-3-8B-Instruct - Audited Hub revision:
852277e5b9534ff51a66adbad1ad43b7a3ef4457 - Public artifact date: August 2024
- Role: rationale-plus-answer generation from supplied evidence
This is a historical Llama 3 artifact. It must not be represented as either revised Llama 3.1 rationale-reader variant described in the updated manuscript.
Model summary
This reader is adapted to generate an intermediate natural-language rationale followed by an answer. The rationale is process supervision generated for task adaptation; it is not a hidden trace recovered from the base model and is not a gold supporting-fact annotation.
Intended use
- Studying natural-language rationale supervision for HotpotQA readers.
- Qualitative inspection of an evidence-conditioned answer path.
- Reader-stage comparisons where evidence is supplied independently.
Out-of-scope use
- Treating generated rationales as faithful explanations or verified proofs.
- Using rationale text as a substitute for HotpotQA supporting-fact labels.
- Open-domain retrieval, safety-critical decisions, or factual verification.
- Associating revised Llama 3.1 rationale results with this legacy checkpoint.
Input and output contract
Input should contain a question and selected, title-preserving evidence. Output is expected to contain rationale text and a final answer. Downstream code must parse the final answer explicitly and must keep rationale evaluation separate from answer/evidence metrics.
The public legacy configuration does not preserve a complete prompt-version manifest or an independently verified rationale delimiter. Do not assume that a newly invented delimiter exactly matches historical training.
Loading
import torch
from transformers import AutoModelForCausalLM, AutoTokenizer
MODEL_ID = "bactrianus/HotpotQA-Reader-CoT-Llama-3-8B-Instruct"
REVISION = "852277e5b9534ff51a66adbad1ad43b7a3ef4457"
tokenizer = AutoTokenizer.from_pretrained(MODEL_ID, revision=REVISION)
model = AutoModelForCausalLM.from_pretrained(
MODEL_ID,
revision=REVISION,
torch_dtype=torch.bfloat16,
device_map="auto",
)
model.eval()Training data and lineage
The checkpoint derives from Meta Llama 3 8B Instruct and HotpotQA-based reader/rationale supervision. Two separately versioned dataset resources are relevant to this task:
- `cot-reader-sft` in the canonical dataset at
v1.0.0is a complete deterministic view with 90,447 unique training source IDs. Its assistant targets serialize indexed gold evidence followed by the reference answer; they are not model-generated rationales. - `teacher-cot-llama31-8b-sft` in the teacher-trace dataset at
v1.0.0contains one resolved Llama 3.1 8B-labelled rationale per source ID for 71,238 training examples. - `teacher-cot-llama31-70b-sft` in the teacher-trace dataset at
v1.0.0contains 28,176 recovered Llama 3.1 70B-labelled records: all 15,661 hard examples and 12,515 medium examples. Each row includes the archived annotation and an SFT conversation joined to the canonical dataset throughsource_id.
from datasets import load_dataset
deterministic_train = load_dataset(
"bactrianus/bactrainus-hotpotqa",
"cot-reader-sft",
split="train",
revision="v1.0.0",
)
teacher_8b_train = load_dataset(
"bactrianus/bactrainus-hotpotqa-teacher-traces",
"teacher-cot-llama31-8b-sft",
split="train",
revision="v1.0.0",
)
teacher_70b_train = load_dataset(
"bactrianus/bactrainus-hotpotqa-teacher-traces",
"teacher-cot-llama31-70b-sft",
split="train",
revision="v1.0.0",
)These resources document the current dataset release; neither is asserted to be byte-identical to the historical training serialization for this legacy Llama 3 checkpoint. The teacher configuration's Llama 3.1 label describes its archived generator record and must not be used to relabel these Llama 3 weights or infer an unrecorded training dependency.
Likewise, the revised reader_8b_rationale_8b.yaml and reader_8b_rationale_70b.yaml files describe Llama 3.1 experiments, not this Llama 3 weight artifact.
Evaluation boundary
No predictions or evaluation results are bundled with this card. The Bactrainus paper reports rationale-supervision experiments with explicit recipe caveats. A correct final answer does not establish rationale faithfulness.
Limitations
- Generated rationales can be post-hoc, incomplete, contradictory, or unsupported.
- Longer outputs increase parsing and truncation risk.
- Evidence omissions propagate to both rationale and answer.
- The model is specialized for English HotpotQA-style inputs.
- Wikipedia-derived data carries temporal and representational biases.
- Historical prompt, generator, and environment details are incomplete.
License and attribution
The weights remain subject to the Meta Llama 3 Community License and Acceptable Use Policy.
Meta Llama 3 is licensed under the Meta Llama 3 Community License, Copyright Meta Platforms, Inc. All Rights Reserved.
Built with Meta Llama 3.
HotpotQA-derived data is licensed under CC BY-SA 4.0. Bactrainus code is Apache-2.0 licensed.
Citation
@article{barati2025bactrainus,
title = {Bactrainus: Optimizing Large Language Models for Multi-hop Complex Question Answering Tasks},
author = {Barati, Iman and Ghafouri, Arash and Minaei-Bidgoli, Behrouz},
journal = {arXiv preprint arXiv:2501.06286},
year = {2025},
doi = {10.48550/arXiv.2501.06286},
url = {https://arxiv.org/abs/2501.06286}
}