Homework 2-A: Word Boundary Segmentation

Umair Z Ahmed (13111166)


Training Corpus

Heliohost corpora for Hindi (containing both Hi_Blogs and Hi_Newspapers) was used to train unigram and bigram models.

Validation Sets

4 random online hindi newspaper articles were taken as validation set and the parameters were tuned to improve the F-Score result. Mainly, setting the max word length (L parameter used in split function in ngrams.py) to 40 resulted in noticeable improvement in F-Score.
The validation input files used are - input1, input2, input3, input4.
And, the corresponding ground truth files are - groundTruth1, groundTruth2, groundTruth3, groundTruth4.

Test Set

The code was finally run on the test set with corresponding groundTruth file. There were few alignment mis-match between the 2 files, which were corrected.

Results

Input Model Precision Recall F-Score
Validation setUniGram 0.891 0.929 0.91
Validation setBiGram 0.897 0.944 0.92
Test setUniGram 0.927 0.94 0.934
Test setBiGram 0.931 0.953 0.942

The complete code used to generate the language models and evaluate the word segmentation can be found on this link.