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Benchmark results, method, limitations and the failure log
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metadata
license: cc-by-4.0
language:
  - am
task_categories:
  - automatic-speech-recognition
pretty_name: Amharic ASR Benchmark
size_categories:
  - 1K<n<10K
tags:
  - amharic
  - ethiopia
  - benchmark
  - evaluation
  - low-resource

Amharic ASR Benchmark

An evaluation of open speech recognition models for Amharic, on a test set that none of them could have trained on, with certain labels and honest statistics.

Published by Dataset.ET.

Results

1,548 clips, 4.72 hours. Greedy decoding. Character error rate, lower is better.

model CER 95% CI WER
badrex/Ethio-ASR-amharic 0.0946 [0.0896, 0.0999] 0.2845 CTC, monolingual Amharic
badrex/Ethio-ASR-multilingual-600M 0.0991 [0.0939, 0.1042] 0.2984 CTC, w2v-BERT 2.0, five Ethiopian languages
b1n1yam/shook-medium-amharic-2k 0.1147 [0.1087, 0.1202] 0.2943 Seq2seq, Whisper medium
badrex/Ethio-ASR-multilingual-1B 0.1308 [0.1249, 0.1366] 0.3894 CTC, MMS-based
b1n1yam/shook-tiny-amharic-stage2-polish 0.2735 [0.2648, 0.2820] 0.6200 Seq2seq, 37.8M parameters

Are the differences real?

Every model is scored on the same 1,548 clips, so comparing marginal confidence intervals is the wrong test — they can overlap while the difference is real. A paired bootstrap over 2,000 resamples of clips:

comparison mean CER difference 95% CI distinguishable
Ethio-ASR-amharic vs Ethio-ASR-multilingual-600M -0.0045 [-0.0067, -0.0022] yes
Ethio-ASR-multilingual-600M vs shook-medium-amharic-2k -0.0155 [-0.0194, -0.0120] yes
shook-medium-amharic-2k vs Ethio-ASR-multilingual-1B -0.0161 [-0.0202, -0.0120] yes
Ethio-ASR-multilingual-1B vs shook-tiny-amharic-stage2-polish -0.1427 [-0.1498, -0.1361] yes

The top two intervals overlap and the difference is still real at p = 0.001. Every adjacent pair here is separable.

What makes this worth trusting

The labels are certain. A contributor was shown a sentence and read it aloud, so the reference existed before the audio. Most speech benchmarks score against transcripts someone typed while listening, which carries an unmeasured error rate of its own.

No model could have seen it. Every model predates the test set by five to nine months, verified against publication timestamps:

asset published
this test set 2026-08-25
badrex/Ethio-ASR-* 2026-03-24
b1n1yam/shook-medium-amharic-2k 2025-12-08
b1n1yam/shook-tiny-* 2025-11-21

Speaker-disjoint splits. No voice appears in more than one split.

The outputs are published. hypotheses/ holds every model's raw transcript for all 1,548 clips. Do not trust these numbers — recompute them.

Three findings worth stating

The 600M model beats the 1B by 24% relative, at 40% of the size. Larger is not better within this family. We had been building on the 1B.

A monolingual model narrowly beats the multilingual one for Amharic specifically: 0.0946 against 0.0991, a real difference. Multilingual training costs a little here rather than helping.

CER and WER disagree about ranking. shook-medium-amharic-2k has worse CER than Ethio-ASR-multilingual-600M (0.1147 vs 0.0991) but better WER (0.2943 vs 0.2984). The sequence-to-sequence model produces fluent whole words that match exactly; the CTC model gets characters closer but whole words slightly off. For an agglutinative language written in Ge'ez script, which metric you choose changes who wins.

Read this before quoting anything

This is one domain: people reading prompts into a phone. On spontaneous speech the same models are far worse — we measured roughly three times the disagreement between them on podcast audio. These are not general Amharic ASR figures. See docs/LIMITATIONS.md.

Decoding is greedy, so every number is a lower bound, and that penalty is not evenly distributed between CTC and sequence-to-sequence models.

What went wrong

docs/FAILURES.md is the honest engineering log: ten failures including three that produced results which looked correct, a health check that reported a working system as broken, and a shutdown timer we triggered by trying to disable it.

It is the most useful document here. Benchmarks are usually published as though they fell out of the sky.

Contents

README.md                    this
docs/METHOD.md               test set, scoring, statistics
docs/FAILURES.md             what went wrong and what it cost
docs/LIMITATIONS.md          read before quoting
results/phase1_greedy.json   the numbers
results/bootstrap.json       intervals and paired tests
hypotheses/                  every model's raw output, per clip
scripts/                     the evaluation code

Reproducing

python scripts/bench_asr.py --push-to <your-repo>
python scripts/bootstrap_ci.py build/am-v0.2.0 hypotheses/

The test set is snapwre/amharic-speech, open under CC BY 4.0.

Citing

@misc{datasetet2026amharicasr,
  title  = {Amharic ASR Benchmark: an uncontaminated evaluation of open speech models},
  author = {Dataset.ET},
  year   = {2026},
  url    = {https://huggingface.co/datasets/snapwre/amharic-asr-benchmark}
}

Contact

Corrections and additional models are welcome — open a discussion. If you built one of these models and think a decoding choice disadvantaged it, say so and we will rerun it.

Chapi, Dataset.ET