Towards a Corpus of Spoken Maltese: Korpus tal-Malti Mitkellem, KMM
Paper · 2024 · Alexandra (Sandra) Vella, Sarah Agius, Aiden Williams et al.
Summary
Maltese is a low-resource language whose existing speech material does not reflect everyday talk. Most of it consists of edited parliamentary transcripts or read-aloud prompts. The authors argue for a purpose-built spoken corpus, Korpus tal-Malti Mitkellem (KMM). Instead of collecting whatever data happens to be available, KMM is planned around representativeness and balance. Its centre is a carefully annotated, gold-standard Core collection. Around it sit two kinds of Satellite material: Donated corpora from earlier projects and Harvested media such as podcasts, radio and TV.
The Core is recorded from volunteers across a planned range of text-types. These run from reading tasks, where the text is known in advance, to prompted, task-oriented and free speech, in monologue (Mono) or dialogue (Dia). About 20 hours have been compiled and annotated by humans so far.
The authors also ran a small qualitative comparison between a Maltese ASR system's output and the human transcripts. The ASR proved good enough to give annotators a first draft, which could cut transcription effort and cost. This matters because high cost is the main reason spoken corpora remain scarce.
Key points
- KMM structure:
- a gold-standard Core collection that can be extended in principled ways;
- Satellite material, split into Donated (from other projects) and Harvested (online programmes, podcasts, broadcasts).
- The current Core holds roughly 20 hours of speech with human annotation.
- Core speaking tasks vary in how scripted they are (read, prompted, task-oriented, free) and in how many speakers take part (Mono vs Dia).
- Existing Maltese speech resources reviewed:
- Korpus Malti v3.0 parliamentary transcripts (c. 43.4M + 50M tokens) and an 18,000-token speeches set;
- Common Voice (18h, half validated);
- MASRI-Headset (8h);
- CommonLanguage (1h);
- smaller corpora such as MalToBI and MAMCO.
- The authors define a spoken corpus in four layers: audio, transcript, time-aligned transcription, and speaker/recording metadata. As context on scarcity, CLARIN lists 133 spoken corpora, but they cover only 15 languages.
Interesting ideas
- I1. Gold core plus satellites. A small, deliberately balanced gold collection sits at the centre, with larger donated or harvested material of lower certainty kept separate from it, so each tier's quality stays known.
- I2. Graded text-types. Data runs from easy cases, where the reference text exists in advance, to fully unscripted speech, giving a built-in difficulty gradient within one resource.
- I3. Machine draft, human correction. Automatic output serves as a first pass that humans edit, and the draft is judged directly against human output to decide whether it actually saves effort.
- I4. Edited records are not natural language. Cleaned-up records such as parliamentary transcripts differ stylistically from real conversation, with rhetorical repetition and different pause and syntax patterns, so they are a poor stand-in for natural usage.
- I5. Layered resource design for several user groups. A minimal layer (audio plus text) serves technology users, while extra layers (alignment, metadata) serve researchers, which spreads the high cost of building the resource across more uses.
For Mova
How these ideas could serve Mova, our small open language model — its files, stages and tests:
- I1 (learn): Keep a small hand-checked gold set strictly apart from silver data agreed by witness parsers, and label each sentence's tier so that training and evaluation never mix the two by accident.
- I2 (answer): Build reader test suites in graded bands, from clean textbook prose to messy dialogue-like text, so drops in accuracy can be traced to a specific difficulty level.
- I3 (learn): Let parsers or the LLM teacher pre-annotate UD trees and frames for human correction, and log the edit distance as a measure of whether the draft tier is worth using.
- I4 (tokens): Do not assume that edited newswire-style English covers conversational input, and add explicit tests for disfluencies, repetitions and fillers in the tokenizer and tagger.
- I5 (world): Store character-span alignment and source metadata alongside every tree node and world entity, so one annotated corpus can support both training and explainable tracing back to the source.
Fields, topics and concepts
📚 Shelves 4The field of science this work belongs to (OpenAlex fields).Computer Science · 16,667 worksArtificial Intelligence · 16,194 worksArts and Humanities · 16,039 worksLanguage and Linguistics · 15,891 works
🧭 Topics 1Research subjects and languages the work is about.Semitic languages · 2,908 works
Cite
Cite as Alexandra (Sandra) Vella, Sarah Agius, Aiden Williams and Claudia Borg. 2024. Towards a Corpus of Spoken Maltese: Korpus tal-Malti Mitkellem, KMM. Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024).
@inproceedings{vella2024corpus,
title = {{Towards a Corpus of Spoken Maltese: Korpus tal-Malti Mitkellem, KMM}},
author = {Alexandra (Sandra) Vella, Sarah Agius, Aiden Williams and Claudia Borg},
booktitle = {Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)},
year = {2024},
doi = {10.63317/5k7ktu5qumgk},
url = {https://doi.org/10.63317/5k7ktu5qumgk}
}References
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