New mathematical model to enable web searches for meaning

Sep 26, 2011

(PhysOrg.com) -- A new theory of meaning has the potential to revolutionise many artificial intelligence technologies and enable web searches that interpret the meaning of queries, according to its developer, a computer scientist at the University of Hertfordshire.

In a paper to be published online in tomorrow, Dr. Daoud Clarke describes how he has built a based on the idea that the meaning of and phrases is determined by the contexts in which they occur.

“This is an old idea, with its origin in the philosophy of Wittgenstein, and was later taken up by linguists,” said Dr. Clarke, “but this is the first time that someone has used it to construct a comprehensive of meaning.”

The model provides a theory about how to represent words and phrases using vectors, or sequences of numbers. A vector identifies a point in some multi-dimensional space, which may have hundreds or thousands of dimensions.

“There are existing techniques which can build these vectors for words by looking at the contexts they occur in, for example on the web. This works well for words or short phrases, but if you want to extend this to long or whole sentences, you quickly run out of data, even on the web. Our theory tells you what the vector for a phrase should look like in terms of the vectors for the individual words that make up the phrase.

“For example, at the moment we may have vectors for 'big' and 'cat', but we don't know the best way to combine them to get a vector for 'big cat',” explained Dr. Clarke. “There are lots of possibilities: for example you could add the two vectors together, but then 'big cat' would have to mean the same as 'cat big', which doesn't make sense.

The value of the theory is in identifying which methods of combining vectors do make sense. Our theory will tell you if your method of combining vectors is consistent with the idea that meaning is determined by context.”

According to Dr. Clarke, most existing theories in this field are based around the idea that the meaning of sentences can be represented in terms of logic, but these cannot capture the subtleties of language, such as the relationship between the words “like” and “love”. Representing meanings of words using vectors allows fuzzy relationships between words to be expressed as the distance or angle between the vectors.

Dr. Clarke believes his theory will have many applications in , in particular helping web search engines understand the meaning of your query. “Google works by looking for the words you type in the documents it knows about,” said Dr Clarke. “If you type in a long phrase or sentence, it just tries to match as many words as possible. Imagine how powerful it could be if it understood the meaning of your query, and tried to match it to the closest in all the documents it knows about.”

Explore further: Researchers help Boston Marathon organizers plan for 2014 race

More information: A Context-theoretic Framework for Compositionality in Distributional Semantics, Computational Linguistics.

Provided by University of Herfordshire

4 /5 (6 votes)

Related Stories

Linguists to re-think reason for short words

Jan 25, 2011

(PhysOrg.com) -- Linguists have thought for many years the length of words is related to the frequency of use, with short words used more often than long ones. Now researchers in the US have shown the length is more closely ...

For English learners, reading isn't always

Apr 11, 2011

(PhysOrg.com) -- An influential model for teaching reading and comprehension to English learners doesn’t work well for Cantonese-speaking children, according to new research from the University of California, Davis, ...

New device provides 'voice' for patients who can't speak

Jul 18, 2011

When Vernia Moore suffered a stroke she took full stock of her functions in the recovery room. Arms and hands moving? Check. Legs and feet okay? Check. Memory intact, with full comprehension? Check, check. ...

Recommended for you

Egypt archaeologists find ancient writer's tomb

19 hours ago

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...

Study finds law dramatically curbing need for speed

Apr 18, 2014

Almost seven years have passed since Ontario's street-racing legislation hit the books and, according to one Western researcher, it has succeeded in putting the brakes on the number of convictions and, more importantly, injuries ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

jburchel
not rated yet Sep 26, 2011
Wittgenstein is lame. That is so early 20th century..
Doug_Huffman
3 / 5 (2) Sep 27, 2011
We stand on the shoulders of giants. Wittgenstein published only the very brief Tractatus to invent logical positivism and inspire philosophy in common language.

Will you do better? Try Bayesian Epistemology.

More news stories

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...