2005年7月31日

Reading(2): Language research, application, evaluation and analysis

I remembered a story about how to be successful. It said that write your tasks today, order them by their importance, finish the first one and keep on, you will be successful. I believed the reason is that if you finish the most important thing, you would be excited and have the passion and potency to finish the others easily.

Following this principle, I listed my tasks today. Because I was in the important process of training my reading habit, I believed the reading task was the most difficult for me.

Now I had finished the first phrase of my reading task. I would like to write some abstract and gain.
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Pages: 1~10 of Natural Language Understanding, second edition, by James F. Allen, 1995

Language research:
There are four main kinds of language researchers, linguist, psychological linguist, philosopher and computational linguist. Under the background of my study, I belonged to the last one. To computational linguist, the typical research problems were how to identify the structure of a sentence, how to modeling for knowledge and reasoning and how to use language for some special tasks. The main tools for us were algorithms, data structure, formal models of representation and reasoning, and artificial intelligence (search and representation methods). Now, I thought, I had mastered most of the tools and be familiar with few of the typical problems. I wished I could be versed on the problems. After all, the problems were the most important for any research.

Language research application:
There were two categories of natural language understanding application: text based and dialogue based. The former was about the processing of text, such as book, newspaper, report, handbook, email. They were all reading based task. The typical applications of this type were finding special topics from text database, information from messages and articles, documents translation, and summarization. The main problem of them was constructing a representation for information of text then used for reasoning.
Dialogue based application was more about the communication between human and computer, such as question answering systems, auto customer service system by telephone, auto teaching system, spoken language control for machines, and synergic problem solving system. They all were based on dialogue and keyboard based alternation.

Language understanding system evaluation: System evaluation included two main types: black box and white box test. Evaluation was very important for NLU and NLP research. If you could not construct the evaluation system, you could not start do your research practically. Black box test should be used after there was high performance of white box test. This was a very important principle. For example, the famous psychoanalyst robot ELIZA had not any intelligence but achieved best performance on psychopath treatment. It was based on keywords. So if you ask some wrong sentences with the keywords, it would answer all the same.

Language analysis:
There were three layers of language analysis: syntax, semantic, and pragmatic.
Syntax considered how to list words for correct sentences, confirm the roles of each works in sentences and the relation between phrases.
Semantic used for researching how to combine the meanings of each word for the meaning of the whole sentence. It was context-free sentence meaning research.
Pragmatic took care about same sentence used in different context and the influence of the context to the sentence meaning.
Up to the three basic layers, there were two main aspects of context: discourse and the world information. The two were all about context. Until now, research on the two layers was hot. Anaphora resolution and Coreference resolution belonged to this kind.
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2 条评论:

  1. Comment's author: Johnny Cui
    08/17/2005 06:18:33 PM
    I like this log which makes me clear about my research area. The definition and categorization are both incisive. It helps a lot.

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  2. Comment's author: Bill_Lang
    08/18/2005 03:10:36 PM
    ^_^,welcome Cui again and again~! You blog is very nice too.

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