<DOC> 
<DOCNO> IRS13 </DOCNO>         
<TITLE> Scientific Report No. IRS-13 Information Storage and Retrieval </TITLE>         
<SUBTITLE> Word-Word Associations in Document Retrieval Systems </SUBTITLE>         
<TYPE> chapter </TYPE>         
<PAGE CHAPTER="9" NUMBER="11">                   
<AUTHOR1> M. E. Lesk </AUTHOR1>  
<PUBLISHER> Harvard University </PUBLISHER> 
<EDITOR1> Gerard Salton </EDITOR1> 
<COPYRIGHT MTH="December" DAY="" YEAR="1967" BY="National Science Foundation">   
Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. 
</COPYRIGHT> 
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                                                                     Ix-"

       Frequency    3     4    5-6    7-8   9-10  11-19   20+   all
       of words

          3        19%   10%   11%    13%   16%    14%    15%   14%

          4               0%    9%     0%   40%    18%    20%   12%

          5-6                  12%    33%   16%    22%    19%   21%

          7-8                          0%    0%    20%     0%    5%

          9-10                               0%    43%    25%   25%

         11-19                                     50%    29%   33%

         20+                                              37%   37%

        Dependence of Word-Pair significance On Word Frequency


                                Table 3


Note:  the `all' column shows the percentage of significant correlations
       among all pairs which have the frequency of their lower frequency
       word indicated by the row frequency; not the percentage among all
       pairs with a word of the indicated frequency either as maximum
       or minimum frequency component.

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