1. Ontologies ARIN Practical W7/Spr Dimitar Kazakov & Suresh Manandhar

2. WordNet You are familiar with the WordNet ontology from the ARIN lectures. To obtain closer, hands- on knowledge of it, follow these exercises:

3. Exercise 1A 1.Visit the online portal to the WN ontology at: http://wordnetweb.princeton.edu/perl/webwn http://wordnetweb.princeton.edu/perl/webwn 2.Enter a noun of your choice as a search item. Click on the S: link against one of the meanings returned and request to see the inherited (=all) hypernyms. Look up the most general one in the list. Check if it has already been published on Twitter: https://twitter.com/gagg_ARIN. If not, submit it, labelling the word with :noun:root. Repeat until you decide there are no more root nodes in this hierarchy (ie, all have been published)S: https://twitter.com/gagg_ARIN

4. Exercise 1B 1.Visit the online portal to the WN ontology at: http://wordnetweb.princeton.edu/perl/webwn http://wordnetweb.princeton.edu/perl/webwn 2.Enter a verb of your choice as a search item. Click on the S: link against one of the meanings returned and request to see the inherited (=all) hypernyms. Look up the most general one in the list. Check if it has already been published on Twitter: https://twitter.com/gagg_ARIN. If not, submit it, labelling the word with :verb:root. Repeat until you decide there are no more root nodes in this hierarchy (ie, all have been published).S: https://twitter.com/gagg_ARIN

5. Exercise 1C Visit the online portal to the WN ontology at: http://wordnetweb.princeton.edu/perl/webwn http://wordnetweb.princeton.edu/perl/webwn 1.Find the meronyms of the word table (piece of furniture) and submit them on Twitter if they are not there. 2.Spend 5 min trying to find the noun, resp. verb which is separated from the root by the largest number of hypernyms. Submit one candidate in the form: word:PoS:depth:list of hypernyms where depth of root = 0.

6. Exercise 1D Visit the online portal to the WN ontology at: http://wordnetweb.princeton.edu/perl/webwn http://wordnetweb.princeton.edu/perl/webwn Find a synset (word) that is a hypernym of each of the following words: temperance, prudence, fortitude, justice, but is not a hypernym of hope and charity. Write an algorithm (in pseudocode) that would achieve the above task in its general form, and search for (=learn!) a concept C, such that:

7. Exercise 1D (2) Input: Set of positive examples P, set of negative examples N. P and N contain WordNet synsets. Return: the most specific semantic concept (synset) C that subsumes all members of P, but none of N. Assume the ontology is represented as a list/table of pairs: (synset, its_hypernym). Assume there is only one direct hypernym per synset, if it helps.