1. LING/C SC 581: Advanced Computational Linguistics
Lecture 5
Jan 24th

2. 2019 HLT Lecture Series Speaker Title Date Tatjana Scheffler
Analyzing Discourse Structure on Social Media
Friday Feb 15th, 3pm, Comm 311.
Marcos Zampieri
Language Variation and Automatic Language Identification. The Case of Dialects and Similar Languages.
Wednesday Feb 20th, noon, room TBA
Adriana Picoral
Investigating Multilingualism through Computational Linguistics.
Wednesday Feb 27th, noon, room TBA
Gus Hahn-Powell
TBA
Wednesday Mar 13th, noon, room TBA
Miikka Silfverberg
Deep Learning for inflectional morphology and phonology
Wednesday Mar 20th, noon, room TBA

3. Administrivia Homework 3 graded
Google Cloud Natural Language is pretty good:
85% of you said so…
Remark:
-None- is a POS tag
it indicates an empty category and its contents should not be part of the input sentence to Google!

4. Last Time
Note on Homework 4
install and test it (no need to report)

5. Last Time
Penn Treebank (PTB) with nltk
~/nltk_data/corpora/ptb

6. Quick Homework 5
In all cases show your work, i.e. how you derived your number
Using:
from nltk.corpus import ptb
ptb.parsed_sents(categories=['news'])
49208 sentences (Wall Street Journal)
.productions()
Q1: how many phrase structure rules are there?
Q2: what are the top 5 unary branching rules?
Q3: what are the top 5 binary branching rules?
Q4: what are the top 5 > binary branching rules?

7. Quick Homework 5

8. Quick Homework 5 Hints: maybe use… Due date:
nested list comprehension to extract all production rules
Counter
.most_common()
Due date:
by the end of next week
one PDF file!