To understand how to represent knowledge in a first-order logic knowledge base in order to successfully answer queries about that knowledge.
To capture, in sufficient detail in order to answer the queries below , the knowledge of and about the following story:
Yesterday John went to the Telshor Albertsons supermarket and bought two pounds of tomatoes and a pound of ground beef.
Start by trying to represent the knowledge of the sentence in a series of assertions (facts) in first-order logic. You should write sentences that have straightforward logical structure. i.e. objects have certain properties, are related in certain ways etc.
Ask yourself the following questions:
· Which categories, objects and relations do I need? What are their parents, siblings an so on? You will need events and temporal ordering among others.
· Where do the categories fit in a more general hierarchy? i.e. you are defining an ontology
· What are the constraints and interrelationships among them?
· How detailed do I need to be about the various concepts?
Try to make your knowledge base as general as possible. For instance don’t say “people buy things from Albertsons” because that won’t help with other supermarkets. Don’t say “Joe made a spaghetti dinner with the tomatoes and ground beef” because that won’t help with anything.
The knowledge base must be able to answer the following questions. Some involve material directly from the story, but most involve background knowledge about supermarkets, buying things etc. i.e. “reading between the lines” of the story.
1. Is John a child or an adult? (Adult)
2. Does John now have at least two tomatoes? (Yes)
3. Did John buy any meat? (Yes)
4. If Mary was buying tomatoes at the same time as John, did he see her? (Yes)
5. Are the tomatoes made in the supermarket? (No)
6. What is John going to do with the tomatoes? (Eat them)
7. Does Albertsons sell deodorant? (Yes)
8. Did John bring any money to the supermarket? (Yes)
9. Does John have less money after going to the supermarket? (Yes)
As well as your knowledge base you should sketch the chain of reasoning for each question to arrive at the right answer. Many of the things you write may be only approximately correct, but don’t worry about that. This project is obviously open-ended. A complete solution, if one exists, would be extremely difficult to develop. However, your knowledge base should be able to answer the 9 questions above.
April 21st, before midnight.