Technology has emerged almost all the domains in our daily life. In computational linguistics, the uses of electronic corpora are very important. Nowadays it is possible to study linguistic phenomena by using statistical analyses: Concordances, collocations and frequencies have great influence in making linguistic researches more available, more adequate and more accurate.
The Association for Computational Linguistics defines computational linguistics as the scientific study of language from a computational perspective. Computational linguistics is a discipline between linguistics and computer science .It is a part of the cognitive sciences and it has a strong relation with artificial intelligence. Computational linguistics originated from the 1950s, where the United States used computers to translate automatically texts from foreign languages into English, particularly Russian scientific journals. Traditionally, computational linguistics was usually performed by computer scientists who had specialized in the application of computers to the processing of a natural language.
Corpus linguistics is the study and analysis of data obtained from a corpus. The main task of the corpus linguist is not only to find the data but to analyse it. Computers are useful, and sometimes indispensable, tools used in this process. Corpus linguistics is based on two main software objects: a corpus, which is the body of data to be investigated, and a concordancer, a tool for searching that corpus. Corpus Linguistics is now seen as the study of linguistic phenomena through large collections of machine-readable texts: corpora. Biber et al (1998:23) said that: "Corpus linguistics makes it possible to identify the meanings of words by looking at their occurrences in natural contexts, rather than relying on intuitions about how a word is used or on incomplete citation collections".
Corpora come in many shapes and sizes, because they are built to serve different purposes. Nowadays 1 million words is fairly small in terms of corpora. We can make a distinction between reference 1 and monitor corpora 2 : The following list shows a very limited sample of corpora's sizes.
Bank of English: about 400 million words.
• COBUILD/Birmingham Corpus: More than 200 million words.
Longman Lancaster corpus: 30 million words. ____________________________ 1 Reference corpora have a fixed size (e.g., the British National Corpus). 2 Monitor corpora are expandable (e.g., the Bank of English).
• British National Corpus (BNC):100 million words.
American National Corpus (ANC): 11.5 million words.
• Brown corpus: 1million words.
• Lancaster-Oslo/Bergen (LOB) corpus: 1 million words.
• Northern Ireland Transcribed Corpus: 400,000 words.
• Corpus of Spoken American English (CSAE):200,000 words.
What is evident is that the size of any corpus depends mainly on the purposes it was Created for, and that this size can vary from some hundred words to some million words.
In reality, a corpus by itself can do nothing at all; it is nothing other than a store of used language. A corpus does not contain new information about language but the software offers us new perspectives. Most readily available software packages process data from a corpus in three ways: showing, frequency, phraseology and collocations. G. Cook (2003:111).
A concordance is a screen display or printout of a chosen word or phrase in its different contexts, with that word or phrase arranged down the centre of the display along with the text that comes before and after it. John Sinclair (1991:32) defines a concordance as a collection of the occurrences of a word-form each in its own textual environment. In the same context S. Hunston (2002:39) says that it is a programme that searches a corpus for a selected word or phrase and presents every instance of that word or phrase in the centre of the computer screen with the words that come before and after it to the left and right. The selected word appearing in the centre of the screen is known as the "node word".
The following example illustrates the 10 concordances of the word computer from Web Concordancer LOB.txt.
1 etition between the analogue computer and the digital computer. To a 2 g made on a Ferranti Mercury Computer at Meteorological Office, Duns 3 unnecessary devices that the computer can be made an economic propos 4 ouch with manufacturers about computer developments of special signi 5 he {0PIW} are compiled by the computer from data sheets (dictionary 6 seen that the problem of the computer is in no way related to the p 7 racy is required the digital computer is the only one to use and ele 8 he {0ACE} digital electronic computer of our laboratory and, further 9 with the help of the digital computer of the University of Toronto. 10 al purpose electronic digital computer to do the job. It is therefore
Firth (1957) stated that "you shall know the word by the company it keeps". The meaning of Firth's citation here is to classify words not only on the basis of their meanings, but also on the basis of their co-occurrence with other words. S. Hunston (2002:12) defines collocation as the statistical tendency of words to cooccur.
Collocation investigations can be a preliminary step for other research questions: investigating the distribution of word senses and uses, and comparing the use of seemingly synonymous words, because languages have many words that are similar, and dictionary definitions often characterise such words as identical or synonymous in meaning, however investigating the use and distribution of synonyms in a corpus allows us to determine their contextual preferences associated with other collocates or associated with register differences.
Many words have meanings that are similar, and yet the words are not able to be substituted one for the other. Dictionaries, which deal with words separately rather than comparatively, can be of little help, but observing typical usages of near synonyms can clarify differences in meaning. S. Hunston (2002:45). The study is about the following synonyms (Sheer, pure, complete, utter and absolute). The first analysis is upon a traditional research (using dictionaries) In this context Partington (1998:33-46) gives examples of intensifying adjectives: "sheer, pure, complete, utter, and absolute". He points out that dictionaries tend to define those words in similar ways, and even give them as synonymous of each other:
-The Collins COBUILD English Dictionary (CCED), suggests that "complete" and "pure" are synonyms of "sheer". -
The Longman Dictionary of Contemporary English (LDOCE) gives "pure" as a synonym of "sheer". -The earlier Collins COBUILD English Language Dictionary (CCELD)
gives "absolute" as a super ordinate of "sheer". In spite of this apparent similarity in meanings, the typical collocates of each adjective differ to quite a considerable degree. For example "sheer" is used with nouns of degree or magnitude (sheer weight, sheer number) often in the pattern (the sheer noun + of noun); e.g. (the sheer weight of noise). The other adjectives do not collocate with these nouns. In addition, "sheer" alone is often used in expressions indicating causality (though sheer insistence; by sheer hard work; because of sheer hard work; his sheer integrity got him though; his enthusiasm and sheer hard work meant that things moved quickly). Partington (1998:36). He ends this analysis by making some statements: "Complete", is used with nouns indicating:
-Absence:(complete ban) -Change:( complete revamping) -Destruction: (complete collapse) -Absolute is used with what Partington calls "hyperbolic" nouns, such as (chaos, disgrace, genius……). Ibid (1998:43) By using corpora we can see immediately that complete is the most used word (12594 times), followed by the adjective absolute (3432 times) , in the 3 rd position we can find that pure is used (3305 times), sheer is used (2028 times) ; however utter is the last position with only a frequency of (652).
The following five tables show the frequencies of the adjectives concerned by registers: In analysing collocation's table we can notice immediately that the words: (white 104, new 18 and public 12) are the most frequent words that collocate with the adjective pure; the word (new 29) collocates most frequently with complete. The first frequent word that collocates with absolute is (best 11); however the adjective utter does not exist in the top 20 words that collocate with the adjectives listed before.
Corpus Linguistics has developed considerably in the last decades due to the great possibilities offered by the natural language processing with computers. The availability of computers and machine-readable texts has made it possible to get data quickly and easily. Linguistic domains are investigated by the use of computers; the results are very amazing if compared with the traditional research methods.