Chinese Unknown Word Recognition for PCFG-LA Parsing

Algorithm 1

Words label propagation algorithm.

Input:

   (i) 𝑇_𝑙={𝑤_𝑖}^𝑙_𝑖=1: labeled texts

   (ii) 𝑇_𝑢={𝑤_𝑖}^𝑙+𝑢_𝑖=𝑙+1: unlabeled texts

   (iii) 𝐸_𝑙={𝑃_𝜃(𝑤_𝑖,𝑡_𝑖)}_{𝑖=1,…,𝑙}: emission probabilities trained by Berkeley parser

Run:

   (1) {𝐺} = construct_POSTagGraph(𝑇_𝑙,𝑇_𝑢)

   (2) {𝑄} = propagate_POSTagProbability({𝐺},𝐸_𝑙)

   (3) {𝐷_𝑙,𝐷_𝑢} = propagate_POSTag({𝑄},𝐸_𝑙,𝑇_𝑢)

   (4) For 𝑖=1,2,…,𝑁

   (5)  {𝑔_𝑖} = construct_latentGraph(𝐷_𝑙, 𝐷_𝑢)

   (6)  𝑞_𝑖 = propagate_latentTagProbability({𝑔_𝑖})

   (7)  𝐸_𝑢 = combine(𝑞_𝑖^𝑁_𝑖=1)

Output:

      𝐸_𝑢={𝑃_𝜃(𝑤_𝑖,𝑡_𝑖)}_{𝑖=1,…,𝑢}: emission probabilities of unknown words

End