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en:eebo:collocations [2016/09/26 02:00] – [Lesson 5: Collocations] kristinavalentinyovaen:eebo:collocations [2018/07/30 14:49] (current) – vaclavcvrcek
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 Thanks to the corpus linguistics, anyone can easily identify which strings of words are established collocations and which are not. A collocation consists of a key word (a node which usually is also [[en:pojmy:kwic|KWIC]] and a contextual word (collocate)).  Thanks to the corpus linguistics, anyone can easily identify which strings of words are established collocations and which are not. A collocation consists of a key word (a node which usually is also [[en:pojmy:kwic|KWIC]] and a contextual word (collocate)). 
  
-Let's try finding collocations of a word such as //bread//. We select EEBO as the corpus we wish to work with and then use a basic query type. After clicking on the search button, concordance lines will appear. //Bread//, a key word, is always located in the middle of the line (higlighted in pink). We then click on the **collocations** button located in the upper menu and select **custom** from the dropdown menu.+Let's try finding collocations of a word such as //bread//. We select [[en:cnk:eebo|EEBO]] as the corpus we wish to work with and then use a basic query type. After clicking on the search button, concordance lines will appear. //Bread//, a key word, is always located in the middle of the line (higlighted in pink). We then click on the **collocations** button located in the upper menu and select **custom** from the dropdown menu.
  
 [{{eebo-9.png?500|Form for collocation candidates}}] [{{eebo-9.png?500|Form for collocation candidates}}]
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 Under the heading **show functions:** we can choose which measures of association we wish to be calculated for //bread//. [[en:pojmy:asociacni_miry|Association measures]] are used to identify which collocations are statistically significant and which are merely coincidental. Each of the measures is sensitive to different kinds of phrases and each might not work in some cases. It is therefore recommended to combine the measures and compare their output. Under the heading **show functions:** we can choose which measures of association we wish to be calculated for //bread//. [[en:pojmy:asociacni_miry|Association measures]] are used to identify which collocations are statistically significant and which are merely coincidental. Each of the measures is sensitive to different kinds of phrases and each might not work in some cases. It is therefore recommended to combine the measures and compare their output.
  
-For example we can select the following measures:**T-score, mutual information (MI) and log likelihood** and select according to which association measure we wish to sort the results. The order of collocation candidates might vary depending on which association measure is selected. Afterwards we click on the **make candidate list** button.+For example, we can select the following measures:**T-score, mutual information (MI) and log likelihood** and select according to which association measure we wish to sort the results. The order of collocation candidates might vary depending on which association measure is selected. Afterwards we click on the **make candidate list** button.
  
  
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 <WRAP round tip 40%> <WRAP round tip 40%>
-Don't worry about the grammatical words and punctuation marks in the first positions. Function words such as prepositions and articles are the most common words in any language and therefore they frequently co-occur with //bread//. As the EEBO corpus is not lemmatized, it is not possible to restrict the search to adjectives and nouns only.+Don't worry about the grammatical words and punctuation marks in the first positions. Function words such as prepositions and articles are the most common words in any language and therefore they frequently co-occur with any word, even //bread//. As the EEBO corpus is not lemmatized, it is not possible to restrict the search to adjectives and nouns only.
 </WRAP> </WRAP>
  
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   * tea    * tea 
   * war   * war
-You can modify the range within which you wish to search for the collocates.+We can always modify the range within which you wish to search for the collocates.
 </WRAP> </WRAP>
  
 ======= Association measures ======= ======= Association measures =======
  
-Association measures are used to identify a collocation.  Each of the measures is sensitive to different kinds of phrases and each might not work in some cases. We will have a look at how  much can the order of collocate candidates vary depending on which  association measure is selected.+Association measures are used to identify a collocation.  Each of the measures is sensitive to different kind of phrases and each might not work in some cases. Consider the following table and  see how  much can the order of the collocate candidates vary depending on which  association measure is selected.
  
 ^ Collocate ^  Frequency  ^  MI  ^  Log likelihood  ^ T-score ^ ^ Collocate ^  Frequency  ^  MI  ^  Log likelihood  ^ T-score ^
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 How can we interpret these results? How can we interpret these results?
-  * **MI** prefers the words with lower frequency and therefore the results may be biased. In our example we can see that the first five positions are filled with spelling variants of the same word. Although the results are not absolutely satisfactory, they provide a proof of an established collocation such as unleavened bread.+  * **MI** prefers words with lower frequency and therefore the results include the word //unleavened// which is used almost exclusively with //bread// or other pastries such as //cake//, //loaf// or //biscuit//. In our example, we can see that the first five positions are filled with the spelling variants of the same word. Although the results are not absolutely satisfactory, they provide a proof of an established collocation such as //unleavened bread//.
   * **T-score** is based on the co-occurrence frequency and therefore the results of T-score and frequency almost coincide. This association measure prefers words with a high frequency and therefore there are mostly grammatical words and punctuation marks in the first positions. Established collocations may be found in the lower positions of the list.   * **T-score** is based on the co-occurrence frequency and therefore the results of T-score and frequency almost coincide. This association measure prefers words with a high frequency and therefore there are mostly grammatical words and punctuation marks in the first positions. Established collocations may be found in the lower positions of the list.
  
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   * The negative numbers indicate the positions preceding the key word, while the positive ones refer to the right positions.   * The negative numbers indicate the positions preceding the key word, while the positive ones refer to the right positions.
   * Minimum frequency in corpus: establishes minimum overall frequency of a unit in order to be included in the collocate list   * Minimum frequency in corpus: establishes minimum overall frequency of a unit in order to be included in the collocate list
-  * Minimum frequency in given range: provided that we specified the context span for collocate search from -3 to 3, then the minimum frequency in given range optiom determines how frequently should an item co-occur with KWIC to be included in the collocate list+  * Minimum frequency in given range: provided that we specified the context span for collocate search from -3 to 3, then the minimum frequency in given range option determines how frequently should an item co-occur with KWIC to be included in the collocate list
 </WRAP> </WRAP>
 +
 +<WRAP round help 40%>
 +Look at the lists of words below. Using the EEBO corpus, find out which words collocate with the following three near synonyms: //godly, divine or sacred//? 
 +</WRAP>
 +
 +Each of the synonyms is used in slightly different contexts as can be inferred  from the three lists of collocates.
 +  * Set the range **from -3 to 3**
 +  * Sort by **logDice**
 +
 +^Near synonyms ^  ^   ^  ^
 +^1st collocate |sorrow|Majesty|Nature|
 +^ 2nd collocate |learned|Majeſty|Providence|
 +^ 3rd collocate |man|Scriptures|Service|
 +^ 4th collocate|Miniſters|Writ|Revelation|
 +^5th collocate |men|Person|humane|
 +
 +----
 +
 +**If you are ready, you can continue to [[en:eebo:morphology1|Lesson 6]].**
 +
 +----
  
  

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