Methods › Natural Language Processing › Subword Segmentation › Unigram Segmentation

Unigram Segmentation

1 paper tagged archive 2025-07-28

Introduced by Taku Kudo in Subword Regularization: Improving Neural Network Translation Models with Multiple Subword Candidates

archive 2025-07-28 Description, source and code snippet are the archive's method entry.

Unigram Segmentation is a subword segmentation algorithm based on a unigram language model. It provides multiple segmentations with probabilities. The language model allows for emulating the noise generated during the segmentation of actual data.

The unigram language model makes an assumption that each subword occurs independently, and consequently, the probability of a subword sequence 𝐱 = (x₁,…,x_M) is formulated as the product of the subword occurrence probabilities p(xᵢ):

P(𝐱) = ∏ᵢ₌₁ᴹ p(xᵢ), ∀i xᵢ ∈𝒱, ∑_(x ∈𝒱) p(x) = 1,

where 𝒱 is a pre-determined vocabulary. The most probable segmentation 𝐱^* for the input sentence X is then given by:

𝐱^* = argmax_(𝐱 ∈𝒮(X)) P(𝐱),

where 𝒮(X) is a set of segmentation candidates built from the input sentence X. 𝐱^* is obtained with the Viterbi algorithm.

PaperSource

Papers archive 2025-07-28

1 shown of 1, newest first. Repository counts are the archive's code-links table. A Syntology line states what Syntology ran from that paper's harvested code; it is per sample and not a correctness claim.

Tasks archive 2025-07-28

6 tasks the archive attaches to papers tagged with this method, by distinct papers. A task without a page in the catalog is plain text.

TaskPapers
Benchmarking1
Domain Generalization1
Machine Translation1
NMT1
Segmentation1
Translation1

Usage over time archive 2025-07-28

Papers per year tagged with Unigram Segmentation: 2022 to 2022, peak 1 1 0 2022: 1 paper 2022
Papers per year the archive tags with this method, by the paper's archive date (1 dated). Bars are counts, not a trend claim.

Components: the archive holds no method-to-method composition, so PwC's Components table cannot be rebuilt; the Papers list carries no Results column for the same reason (the archive does not join its leaderboard rows to method tags).

Categories archive 2025-07-28

Subword Segmentation

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