MYTH-1.5B inherits complementary strengths from its source models:
Table with columns: Benchmark, DeepSeek-R1 1.5B, Qwen-Coder 1.5B, MYTH-1.5B, Description| Benchmark | DeepSeek-R1 1.5B | Qwen-Coder 1.5B | MYTH-1.5B | Description |
|---|
| MMLU | 61.5 | 63.0 | 62.5 | Knowledge & understanding |
| GSM8K | 84.0 | 72.0 | 79.0 | Math word problems |
| MATH-500 | 83.9 | 52.0 | 72.0 | Competition mathematics |
| HumanEval | 45.0 | 46.8 | 52.0 | Code generation |
| BBH | 52.0 | 44.0 | 50.0 | Hard reasoning tasks |
| MBPP | 38.0 | 42.0 | 45.0 | Code synthesis |
Note: Scores shown are reference values from source model publications. MYTH-1.5B estimates are based on weighted SLERP interpolation. Actual performance may vary. We recommend running your own evaluations.
🧠 Capability Profile
MYTH-1.5B delivers a balanced capability profile across six key dimensions:
Table with columns: Capability, Score, Strength| Capability | Score | Strength |
|---|
| Reasoning | 85 | Deep chain-of-thought from R1 distillation |
| Coding | 78 | Code understanding from Qwen-Coder lineage |
| Mathematics | 80 | Strong math from both source models |
| Knowledge | 62 | General knowledge (1.5B class) |
| Instruction Following | 80 | Clean alignment inherited from both sources |
|
MYTH-1.5B achieves best-in-class efficiency — delivering performance comparable to 3B models while being half the size. This makes it ideal for:
- 🖥️ Edge deployment on CPU or low-power devices
- 📱 Mobile inference via ONNX / GGUF quantization
- ⚡ Low-latency applications where speed matters
- 💰 Cost-effective serving at scale
🔬 Fusion Method: SLERP
MYTH uses Spherical Linear Interpolation (SLERP) — a mathematically principled merging technique that operates directly on model weights:
- Tensor-by-tensor processing — each weight matrix is interpolated independently in high-dimensional space
- Weighted combination — default 0.5/0.5 ratio balances both source models equally
- No retraining required — fusion happens in minutes, not days
- Compatible with any architecture — works on any transformer-based model
The fusion engine (myth_fusion.py) is a lightweight, dependency-minimal Python tool that:
- Reads safetensors directly without mmap
- Processes one tensor at a time (low RAM usage)
- Outputs standard safetensors + config
- Handles sharded models automatically
🚀 Quick Start
Download
# Direct from HuggingFace
git lfs install
git clone https://huggingface.co/dracko14/MYTH-1.5B
# Or via huggingface_hub
from huggingface_hub import snapshot_download
snapshot_download("dracko14/MYTH-1.5B")
from transformers import AutoModelForCausalLM, AutoTokenizer
import torch
model_name = "dracko14/MYTH-1.5B"
tokenizer = AutoTokenizer.from_pretrained(model_name, trust_remote_code=True)
model = AutoModelForCausalLM.from_pretrained(
model_name,
torch_dtype=torch.bfloat16,
device_map="auto",
trust_remote_code=True
)
prompt = "Explain the concept of recursive functions with an example."
inputs = tokenizer(prompt, return_tensors="pt").to(model.device)
outputs = model.generate(
**inputs,
max_new_tokens=512,
temperature=0.7,
do_sample=True
)
print(tokenizer.decode(outputs[0], skip_special_tokens=True))
Quantized (GGUF) for llama.cpp
# Download GGUF version (coming soon)
# Chat via llama.cpp
./llama-cli -m MYTH-1.5B-Q4_K_M.gguf -p "Explain recursion" -n 512 --temp 0.7
🧪 Use Cases
Table with columns: Domain, Strength, Example| Domain | Strength | Example |
|---|
| 💻 Code Generation | ★★★★☆ | Write functions, debug code, explain algorithms |
| 📐 Mathematics | ★★★★☆ | Solve equations, explain proofs, analyze data |
| 🧠 Reasoning | ★★★★★ | Chain-of-thought, logic puzzles, step-by-step analysis |
| 📝 General QA | ★★★☆☆ | Knowledge questions, explanations |
| 📖 Instruction Following | ★★★★☆ | Follow complex multi-step instructions |
📦 Model Lineage
DeepSeek-R1-Distill-Qwen-1.5B Qwen2.5-Coder-1.5B-Instruct
│ │
│ ╭─────────────────╮ │
└─────────┤ SLERP FUSION ├──────────┘
│ (0.5 / 0.5) │
╰────────┬────────╯
│
┌──────▼──────┐
│ MYTH-1.5B │
│ 339 tens │
│ 3.55 GB │
└─────────────┘
- DeepSeek-R1-Distill-Qwen-1.5B (MIT) → Deep reasoning, chain-of-thought, mathematical excellence
- Qwen2.5-Coder-1.5B-Instruct (Apache 2.0) → Code generation, instruction following, structured output
⚠️ Limitations
- 1.5B parameter scale — not competitive with 7B+ models on knowledge-heavy tasks
- Knowledge cutoff — inherits limitations from source model training data
- No multimodal — text-only model
- Evaluations pending — benchmark scores shown are estimates based on source model performance; independent evaluation is recommended
📚 Citation
@software{myth-1.5b,
author = {dracko14},
title = {MYTH-1.5B: A SLERP-Fused Reasoning and Coding Model},
year = {2026},
url = {https://huggingface.co/dracko14/MYTH-1.5B}
}
🙏 Acknowledgements
- DeepSeek for the R1 distillation models
- Qwen Team (Alibaba) for the Qwen2.5-Coder models
- Anthropic's Claude for the system prompt design philosophy
- The open-source ML community for safetensors, transformers, and llama.cpp