Evaluation
Deterministic held-out set of 3,000 pairs (seed=42),
decoded greedily (do_sample=False, no repetition penalty), scored with sacreBLEU:
Table with columns: Direction, sacreBLEU, chrF| Direction | sacreBLEU | chrF |
|---|
| English → Egyptian | 5.05 | 25.62 |
| Egyptian → English | 10.09 | 27.37 |
Saved weights are the best checkpoint by validation loss (eval_loss = 2.467). 20 samples
per direction with references are in eval_bidirectional.json.
Example translations
Real greedy-decoded outputs from the held-out set:
English → Egyptian
Table with columns: Source, Model output, Reference| Source | Model output | Reference |
|---|
| So what should I get you? Should I get you this or that? Just imagine the scene: sitting now, wearing a sleeveless under | يعني إيه اللي أقدر أجي لك؟ أنا هاخدك ده ولا دي؟ حتى لو اتنين، اتنين، شوفتوا شوية شوية من الفلوس، كل واحد هيبقى فيه حاجات | طب أجيب لك إيه؟ أجيب لك دي ولا دي؟ تخيل كده المنظر، قاعد دلوقتي لابس فانلة بحمالات وبتاكل أحلى حتة لحمة ممكن تكلها في حي |
| Prayer niches (mihrabs) | مفيش أي حاجة | محاريب الصلاة |
Egyptian → English
Table with columns: Source, Model output, Reference| Source | Model output | Reference |
|---|
| طب أجيب لك إيه؟ أجيب لك دي ولا دي؟ تخيل كده المنظر، قاعد دلوقتي لابس فانلة بحمالات وبتاكل أحلى حتة لحمة ممكن تكلها في حي | Well, what do you get to you? So if you get to you, it's not like this, it's just what's going on inside, she's just wai | So what should I get you? Should I get you this or that? Just imagine the scene: sitting now, wearing a sleeveless under |
| محاريب الصلاة | My dear, the way I'm going to see. | Prayer niches (mihrabs) |
Usage
ChatML format. Pick the system prompt for the direction you want:
import torch
from transformers import AutoModelForCausalLM, AutoTokenizer
model_id = "oddadmix/Emhotob-5M-Egyptian-English-v2"
tok = AutoTokenizer.from_pretrained(model_id)
model = AutoModelForCausalLM.from_pretrained(model_id, dtype=torch.bfloat16).to("cuda").eval()
SYSTEM = "أنت مترجم محترف. ترجم النص الإنجليزي إلى اللهجة المصرية العامية."
def translate(text, system=SYSTEM):
prompt = (f"<|im_start|>system\n{system}<|im_end|>\n"
f"<|im_start|>user\n{text.strip()}<|im_end|>\n<|im_start|>assistant\n")
ids = tok(prompt, return_tensors="pt", add_special_tokens=False).to(model.device)
if tok.bos_token_id is not None:
bos = torch.tensor([[tok.bos_token_id]], device=model.device)
ids["input_ids"] = torch.cat([bos, ids["input_ids"]], dim=1)
ids["attention_mask"] = torch.cat([torch.ones_like(bos), ids["attention_mask"]], dim=1)
out = model.generate(**ids, max_new_tokens=256, do_sample=False,
eos_token_id=tok.eos_token_id, pad_token_id=tok.pad_token_id)
return tok.decode(out[0, ids["input_ids"].size(1):], skip_special_tokens=True).strip()
Training
- Base model:
oddadmix/Emhotob-5M-v2 (Llama arch, hidden 128, 5 layers, 4 heads, vocab 32000, tied embeddings;
5,080,704 params after resizing for 2 ChatML tokens)
- Dataset:
oddadmix/egyptian-translation-dataset-2.9-openai-batch
- Method: HuggingFace
Trainer, ChatML, prompt-masked cross-entropy (loss only on the
assistant turn). Each row is exploded into two training examples (one per direction).
- Hyperparameters: 3 epochs · effective batch 64 · LR 3e-4 (cosine, 5% warmup) ·
bf16 · max length 1024 ·
load_best_model_at_end on eval_loss.
- Eval split: 3,000 deterministic held-out pairs (
seed=42), scored both directions.
Out-of-domain evaluation — Egyptian Arabic Translation Benchmark
The results above are in-domain: a held-out split of the same corpus this model was
trained on. The numbers below are out-of-domain — the same model scored on the
Egyptian Arabic Translation Benchmark
(oddadmix/egyptian-arabic-translation-benchmark, 319 English→Egyptian pairs written by a different annotator with different
orthographic conventions).
Expect these to be substantially lower than the in-domain scores. That gap is the
generalization penalty, not a regression — both numbers are real, they measure different things.
Table with columns: Metric, Score| Metric | Score |
|---|
BLEU (evaluate, 0–1 — leaderboard metric) | 0.0108 |
| BLEU (sacrebleu, 0–100) | 1.08 |
| chrF | 22.19 |
| METEOR | 0.1352 |
Decoding is deterministic greedy (do_sample=False, no repetition penalty), using the
exact ChatML prompt format the model was trained with — the same protocol as every other
number in this study.
Where this rung sits
Table with columns: Model, Params, BLEU (hf), BLEU (sacre), chrF, METEOR| Model | Params | BLEU (hf) | BLEU (sacre) | chrF | METEOR |
|---|
| 5M v1 | 5.2M | 0.0000 | 0.19 | 13.00 | 0.0558 |
| 5M v2 (this model) | 5.2M | 0.0108 | 1.08 | 22.19 | 0.1352 |
| 10M v1 | 11.2M |
Reading these numbers
BLEU understates quality on this set. Scoring is against a single reference, so a correct
translation that picks a different valid word is penalized — e.g. فريش vs the reference's
طازة for "fresh", or التليفون اللي ضاع vs تليفونها الضايع for "her lost phone". Both are
good Egyptian; only one matches the reference. chrF and METEOR track perceived quality more
closely here.
At 319 rows, differences of roughly 1–2 BLEU between adjacent rungs are within noise.
These are small models — 5M to 50M parameters, orders of magnitude below the large systems
typically evaluated on this benchmark. The result of interest is the scaling curve and
per-parameter efficiency, not absolute rank against models 100–1000× the size.
Limitations
A ~5.1M model: reliable on short/common sentences, but drift, repetition, and errors appear
on long or rare inputs. Gender is disambiguated only from context. For fluent translation use the
50M sibling.
License
Apache-2.0, inherited from the base model.