Evaluation
Evaluated on a 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 | 9.82 | 34.22 |
| Egyptian → English | 16.69 | 36.07 |
The saved weights are the best checkpoint by validation loss (eval_loss = 2.003, epoch 3 of 3).
For reference, the 50M sibling scores BLEU ~24 (en→egy) / ~34 (egy→en) with the same data and eval;
at 5M this pair scored <2 both ways.
Example translations
Real greedy-decoded outputs from the held-out set:
English → Egyptian
Table with columns: English input, Model output (Egyptian), Reference| English input | Model output (Egyptian) | Reference |
|---|
| So what should I get you? Should I get you this or that? | يعني إيه اللي ياخدك؟ أخدك كده ولا ده؟ … | طب أجيب لك إيه؟ أجيب لك دي ولا دي؟ … |
Egyptian → English
Table with columns: Egyptian input, Model output (English), Reference| Egyptian input | Model output (English) | Reference |
|---|
| طب أجيب لك إيه؟ أجيب لك دي ولا دي؟ | Well, what do you get to you? Just go to you, or is… | So what should I get you? Should I get you this or that? |
Short, common exchanges come out well and the model reliably picks the right language; longer
inputs still drift or repeat. 20 samples per direction with references are in
eval_bidirectional.json.
Usage
ChatML format. Pick the system prompt for the direction you want:
import torch
from transformers import AutoModelForCausalLM, AutoTokenizer
model_id = "oddadmix/Emhotob-10M-Egyptian-English-v1"
tok = AutoTokenizer.from_pretrained(model_id)
model = AutoModelForCausalLM.from_pretrained(model_id, dtype=torch.bfloat16).to("cuda").eval()
SYS_TO_EGY = "أنت مترجم محترف. ترجم النص الإنجليزي إلى اللهجة المصرية العامية."
SYS_TO_EN = "You are a professional translator. Translate the Egyptian Arabic text into English."
def translate(text: str, system: str) -> str:
prompt = (
f"<|im_start|>system\n{system}<|im_end|>\n"
f"<|im_start|>user\n{text.strip()}<|im_end|>\n"
f"<|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()
print(translate("I will be fine, don't worry", SYS_TO_EGY))
Training
- Base model:
oddadmix/Emhotob-10M (Llama arch, hidden 256, 4 layers, 8 heads, vocab 32000,
tied embeddings; 10,947,328 params after resizing for 2 ChatML tokens)
- Dataset:
oddadmix/egyptian-translation-dataset-2.9-openai-batch (135,282 rows,
English/Arabic columns; Arabic = Egyptian colloquial)
- 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).
Two ChatML special tokens (<|im_start|>, <|im_end|>) were added and embeddings resized.
- Hyperparameters: 3 epochs · effective batch 64 · LR 3e-4 (cosine, 5% warmup) ·
bf16 · max length 1024 ·
load_best_model_at_end on eval_loss.
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) | 0.0313 |
| BLEU (sacrebleu, 0–100) | 3.13 |
| chrF | 28.52 |
| METEOR | 0.1985 |
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 | 5.2M | 0.0108 | 1.08 | 22.19 | 0.1352 |
| 10M v1 (this model) | 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
- An 11M model: usable on short/common sentences but drift, repetition, and meaning loss appear
on longer or rarer inputs.
- Gender is disambiguated only from context; ambiguous inputs may default one way.
- For fluent translation use
oddadmix/50M-Egyptian-English-v1.
License
Apache-2.0, inherited from the base model.