Document (#22768)

Author

Mather, L.A.

Title

¬A linear algebra measure of cluster quality

Source

Journal of the American Society for Information Science. 51(2000) no.7, S.602-613

Year

2000

Abstract

One of the most common models in information retrieval (IR), the vector space model, represents a document set as a term-document matrix where each row corresponds to a term and each column corresponds to a document. Because of the use of matrices in IR, it is possible to apply linear algebra to this IR model. This paper describes an application of linear algebra to text clustering, namely, a metric for measuring cluster quality. The metric is based on the theory that cluster quality is proportional to the number of terms that are disjoint across the clusters. The metric compares the singular values of the term-document matrix to the singular values of the matrices for each of the clusters to determine the amount of overlap of the terms across clusters. Because the metric can be difficult to interpret, a standardization of the metric is defined, which specifies the number of standard deviations a clustering of that document set. Empirical evidence shows that the standard cluster metric correlates with clustered retrieval performance when comparing clustering algorithms or multiple parameters for the same clustering algorithms

Similar documents (content)

1. Zamir, O.; Etzioni, O.: Grouper : a dynamic clustering interface to Web search results (1999) 0.29

   0.2937652 = sum of:
     0.2937652 = product of:
       0.9180162 = sum of:
         0.006836081 = weight(abstract_txt:that in 207) [ClassicSimilarity], result of:
           0.006836081 = score(doc=207,freq=1.0), product of:
             0.036999676 = queryWeight, product of:
               1.1203749 = boost
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.013964176 = queryNorm
             0.18476056 = fieldWeight in 207, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
         0.04785817 = weight(abstract_txt:algorithms in 207) [ClassicSimilarity], result of:
           0.04785817 = score(doc=207,freq=1.0), product of:
             0.10746999 = queryWeight, product of:
               1.3501842 = boost
               5.7000527 = idf(docFreq=403, maxDocs=44421)
               0.013964176 = queryNorm
             0.4453166 = fieldWeight in 207, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.7000527 = idf(docFreq=403, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
         0.02706316 = weight(abstract_txt:each in 207) [ClassicSimilarity], result of:
           0.02706316 = score(doc=207,freq=1.0), product of:
             0.08412644 = queryWeight, product of:
               1.4630572 = boost
               4.1177115 = idf(docFreq=1965, maxDocs=44421)
               0.013964176 = queryNorm
             0.32169622 = fieldWeight in 207, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.1177115 = idf(docFreq=1965, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
         0.0776673 = weight(abstract_txt:quality in 207) [ClassicSimilarity], result of:
           0.0776673 = score(doc=207,freq=4.0), product of:
             0.10702512 = queryWeight, product of:
               1.650205 = boost
               4.6444306 = idf(docFreq=1160, maxDocs=44421)
               0.013964176 = queryNorm
             0.7256923 = fieldWeight in 207, product of:
               2.0 = tf(freq=4.0), with freq of:
                 4.0 = termFreq=4.0
               4.6444306 = idf(docFreq=1160, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
         0.18605912 = weight(abstract_txt:clusters in 207) [ClassicSimilarity], result of:
           0.18605912 = score(doc=207,freq=3.0), product of:
             0.21089864 = queryWeight, product of:
               2.316498 = boost
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.013964176 = queryNorm
             0.88222057 = fieldWeight in 207, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
         0.07234459 = weight(abstract_txt:document in 207) [ClassicSimilarity], result of:
           0.07234459 = score(doc=207,freq=2.0), product of:
             0.15248385 = queryWeight, product of:
               2.542912 = boost
               4.29415 = idf(docFreq=1647, maxDocs=44421)
               0.013964176 = queryNorm
             0.47444102 = fieldWeight in 207, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               4.29415 = idf(docFreq=1647, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
         0.24884228 = weight(abstract_txt:clustering in 207) [ClassicSimilarity], result of:
           0.24884228 = score(doc=207,freq=4.0), product of:
             0.2560094 = queryWeight, product of:
               2.947083 = boost
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.013964176 = queryNorm
             0.9720045 = fieldWeight in 207, product of:
               2.0 = tf(freq=4.0), with freq of:
                 4.0 = termFreq=4.0
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
         0.2513455 = weight(abstract_txt:cluster in 207) [ClassicSimilarity], result of:
           0.2513455 = score(doc=207,freq=3.0), product of:
             0.2836613 = queryWeight, product of:
               3.102162 = boost
               6.548176 = idf(docFreq=172, maxDocs=44421)
               0.013964176 = queryNorm
             0.88607603 = fieldWeight in 207, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               6.548176 = idf(docFreq=172, maxDocs=44421)
               0.078125 = fieldNorm(doc=207)
       0.32 = coord(8/25)
   

2. Dang, E.K.F.; Luk, R.W.P.; Ho, K.S.; Chan, S.C.F.; Lee, D.L.: ¬A new measure of clustering effectiveness : algorithms and experimental studies (2008) 0.27

   0.27435973 = sum of:
     0.27435973 = product of:
       0.97985613 = sum of:
         0.11037266 = weight(abstract_txt:disjoint in 2367) [ClassicSimilarity], result of:
           0.11037266 = score(doc=2367,freq=1.0), product of:
             0.131854 = queryWeight, product of:
               1.0575017 = boost
               8.928879 = idf(docFreq=15, maxDocs=44421)
               0.013964176 = queryNorm
             0.8370824 = fieldWeight in 2367, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               8.928879 = idf(docFreq=15, maxDocs=44421)
               0.09375 = fieldNorm(doc=2367)
         0.008203297 = weight(abstract_txt:that in 2367) [ClassicSimilarity], result of:
           0.008203297 = score(doc=2367,freq=1.0), product of:
             0.036999676 = queryWeight, product of:
               1.1203749 = boost
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.013964176 = queryNorm
             0.22171268 = fieldWeight in 2367, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.09375 = fieldNorm(doc=2367)
         0.05742981 = weight(abstract_txt:algorithms in 2367) [ClassicSimilarity], result of:
           0.05742981 = score(doc=2367,freq=1.0), product of:
             0.10746999 = queryWeight, product of:
               1.3501842 = boost
               5.7000527 = idf(docFreq=403, maxDocs=44421)
               0.013964176 = queryNorm
             0.53437996 = fieldWeight in 2367, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.7000527 = idf(docFreq=403, maxDocs=44421)
               0.09375 = fieldNorm(doc=2367)
         0.22327094 = weight(abstract_txt:clusters in 2367) [ClassicSimilarity], result of:
           0.22327094 = score(doc=2367,freq=3.0), product of:
             0.21089864 = queryWeight, product of:
               2.316498 = boost
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.013964176 = queryNorm
             1.0586647 = fieldWeight in 2367, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.09375 = fieldNorm(doc=2367)
         0.1952925 = weight(abstract_txt:linear in 2367) [ClassicSimilarity], result of:
           0.1952925 = score(doc=2367,freq=2.0), product of:
             0.22080375 = queryWeight, product of:
               2.3702724 = boost
               6.6710296 = idf(docFreq=152, maxDocs=44421)
               0.013964176 = queryNorm
             0.8844619 = fieldWeight in 2367, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               6.6710296 = idf(docFreq=152, maxDocs=44421)
               0.09375 = fieldNorm(doc=2367)
         0.21114966 = weight(abstract_txt:clustering in 2367) [ClassicSimilarity], result of:
           0.21114966 = score(doc=2367,freq=2.0), product of:
             0.2560094 = queryWeight, product of:
               2.947083 = boost
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.013964176 = queryNorm
             0.8247731 = fieldWeight in 2367, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.09375 = fieldNorm(doc=2367)
         0.17413726 = weight(abstract_txt:cluster in 2367) [ClassicSimilarity], result of:
           0.17413726 = score(doc=2367,freq=1.0), product of:
             0.2836613 = queryWeight, product of:
               3.102162 = boost
               6.548176 = idf(docFreq=172, maxDocs=44421)
               0.013964176 = queryNorm
             0.6138915 = fieldWeight in 2367, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               6.548176 = idf(docFreq=172, maxDocs=44421)
               0.09375 = fieldNorm(doc=2367)
       0.28 = coord(7/25)
   

3. Zhu, W.Z.; Allen, R.B.: Document clustering using the LSI subspace signature model (2013) 0.27

   0.27232903 = sum of:
     0.27232903 = product of:
       0.7564695 = sum of:
         0.047331452 = weight(abstract_txt:standard in 1690) [ClassicSimilarity], result of:
           0.047331452 = score(doc=1690,freq=3.0), product of:
             0.073967785 = queryWeight, product of:
               1.1201359 = boost
               4.7288613 = idf(docFreq=1066, maxDocs=44421)
               0.013964176 = queryNorm
             0.6398928 = fieldWeight in 1690, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               4.7288613 = idf(docFreq=1066, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.006836081 = weight(abstract_txt:that in 1690) [ClassicSimilarity], result of:
           0.006836081 = score(doc=1690,freq=1.0), product of:
             0.036999676 = queryWeight, product of:
               1.1203749 = boost
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.013964176 = queryNorm
             0.18476056 = fieldWeight in 1690, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.033905342 = weight(abstract_txt:across in 1690) [ClassicSimilarity], result of:
           0.033905342 = score(doc=1690,freq=1.0), product of:
             0.08540735 = queryWeight, product of:
               1.2036412 = boost
               5.081394 = idf(docFreq=749, maxDocs=44421)
               0.013964176 = queryNorm
             0.39698392 = fieldWeight in 1690, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.081394 = idf(docFreq=749, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.04785817 = weight(abstract_txt:algorithms in 1690) [ClassicSimilarity], result of:
           0.04785817 = score(doc=1690,freq=1.0), product of:
             0.10746999 = queryWeight, product of:
               1.3501842 = boost
               5.7000527 = idf(docFreq=403, maxDocs=44421)
               0.013964176 = queryNorm
             0.4453166 = fieldWeight in 1690, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.7000527 = idf(docFreq=403, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.07400469 = weight(abstract_txt:term in 1690) [ClassicSimilarity], result of:
           0.07400469 = score(doc=1690,freq=3.0), product of:
             0.11406331 = queryWeight, product of:
               1.7036015 = boost
               4.794713 = idf(docFreq=998, maxDocs=44421)
               0.013964176 = queryNorm
             0.64880365 = fieldWeight in 1690, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               4.794713 = idf(docFreq=998, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.13419867 = weight(abstract_txt:matrices in 1690) [ClassicSimilarity], result of:
           0.13419867 = score(doc=1690,freq=1.0), product of:
             0.21370529 = queryWeight, product of:
               1.9039565 = boost
               8.037906 = idf(docFreq=38, maxDocs=44421)
               0.013964176 = queryNorm
             0.6279614 = fieldWeight in 1690, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               8.037906 = idf(docFreq=38, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.14777336 = weight(abstract_txt:singular in 1690) [ClassicSimilarity], result of:
           0.14777336 = score(doc=1690,freq=1.0), product of:
             0.22788402 = queryWeight, product of:
               1.9661034 = boost
               8.30027 = idf(docFreq=29, maxDocs=44421)
               0.013964176 = queryNorm
             0.6484586 = fieldWeight in 1690, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               8.30027 = idf(docFreq=29, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.08860367 = weight(abstract_txt:document in 1690) [ClassicSimilarity], result of:
           0.08860367 = score(doc=1690,freq=3.0), product of:
             0.15248385 = queryWeight, product of:
               2.542912 = boost
               4.29415 = idf(docFreq=1647, maxDocs=44421)
               0.013964176 = queryNorm
             0.5810692 = fieldWeight in 1690, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               4.29415 = idf(docFreq=1647, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
         0.17595807 = weight(abstract_txt:clustering in 1690) [ClassicSimilarity], result of:
           0.17595807 = score(doc=1690,freq=2.0), product of:
             0.2560094 = queryWeight, product of:
               2.947083 = boost
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.013964176 = queryNorm
             0.68731093 = fieldWeight in 1690, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.078125 = fieldNorm(doc=1690)
       0.36 = coord(9/25)
   

4. Dunlavy, D.M.; O'Leary, D.P.; Conroy, J.M.; Schlesinger, J.D.: QCS: A system for querying, clustering and summarizing documents (2007) 0.26

   0.26121995 = sum of:
     0.26121995 = product of:
       0.7256109 = sum of:
         0.019128779 = weight(abstract_txt:standard in 1947) [ClassicSimilarity], result of:
           0.019128779 = score(doc=1947,freq=1.0), product of:
             0.073967785 = queryWeight, product of:
               1.1201359 = boost
               4.7288613 = idf(docFreq=1066, maxDocs=44421)
               0.013964176 = queryNorm
             0.2586096 = fieldWeight in 1947, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.7288613 = idf(docFreq=1066, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.004785257 = weight(abstract_txt:that in 1947) [ClassicSimilarity], result of:
           0.004785257 = score(doc=1947,freq=1.0), product of:
             0.036999676 = queryWeight, product of:
               1.1203749 = boost
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.013964176 = queryNorm
             0.1293324 = fieldWeight in 1947, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.02373374 = weight(abstract_txt:across in 1947) [ClassicSimilarity], result of:
           0.02373374 = score(doc=1947,freq=1.0), product of:
             0.08540735 = queryWeight, product of:
               1.2036412 = boost
               5.081394 = idf(docFreq=749, maxDocs=44421)
               0.013964176 = queryNorm
             0.27788875 = fieldWeight in 1947, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.081394 = idf(docFreq=749, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.042360544 = weight(abstract_txt:each in 1947) [ClassicSimilarity], result of:
           0.042360544 = score(doc=1947,freq=5.0), product of:
             0.08412644 = queryWeight, product of:
               1.4630572 = boost
               4.1177115 = idf(docFreq=1965, maxDocs=44421)
               0.013964176 = queryNorm
             0.50353426 = fieldWeight in 1947, product of:
               2.236068 = tf(freq=5.0), with freq of:
                 5.0 = termFreq=5.0
               4.1177115 = idf(docFreq=1965, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.0751949 = weight(abstract_txt:clusters in 1947) [ClassicSimilarity], result of:
           0.0751949 = score(doc=1947,freq=1.0), product of:
             0.21089864 = queryWeight, product of:
               2.316498 = boost
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.013964176 = queryNorm
             0.3565452 = fieldWeight in 1947, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.050641213 = weight(abstract_txt:document in 1947) [ClassicSimilarity], result of:
           0.050641213 = score(doc=1947,freq=2.0), product of:
             0.15248385 = queryWeight, product of:
               2.542912 = boost
               4.29415 = idf(docFreq=1647, maxDocs=44421)
               0.013964176 = queryNorm
             0.3321087 = fieldWeight in 1947, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               4.29415 = idf(docFreq=1647, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.12317064 = weight(abstract_txt:clustering in 1947) [ClassicSimilarity], result of:
           0.12317064 = score(doc=1947,freq=2.0), product of:
             0.2560094 = queryWeight, product of:
               2.947083 = boost
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.013964176 = queryNorm
             0.48111764 = fieldWeight in 1947, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.17594184 = weight(abstract_txt:cluster in 1947) [ClassicSimilarity], result of:
           0.17594184 = score(doc=1947,freq=3.0), product of:
             0.2836613 = queryWeight, product of:
               3.102162 = boost
               6.548176 = idf(docFreq=172, maxDocs=44421)
               0.013964176 = queryNorm
             0.6202532 = fieldWeight in 1947, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               6.548176 = idf(docFreq=172, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
         0.210654 = weight(abstract_txt:metric in 1947) [ClassicSimilarity], result of:
           0.210654 = score(doc=1947,freq=1.0), product of:
             0.5280455 = queryWeight, product of:
               5.1837697 = boost
               7.2947483 = idf(docFreq=81, maxDocs=44421)
               0.013964176 = queryNorm
             0.39893156 = fieldWeight in 1947, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               7.2947483 = idf(docFreq=81, maxDocs=44421)
               0.0546875 = fieldNorm(doc=1947)
       0.36 = coord(9/25)
   

5. Kostoff, R.N.; Block, J.A.: Factor matrix text filtering and clustering (2005) 0.21

   0.21366242 = sum of:
     0.21366242 = product of:
       0.66769505 = sum of:
         0.0118404385 = weight(abstract_txt:that in 4683) [ClassicSimilarity], result of:
           0.0118404385 = score(doc=4683,freq=3.0), product of:
             0.036999676 = queryWeight, product of:
               1.1203749 = boost
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.013964176 = queryNorm
             0.32001466 = fieldWeight in 4683, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               2.3649352 = idf(docFreq=11344, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
         0.033905342 = weight(abstract_txt:across in 4683) [ClassicSimilarity], result of:
           0.033905342 = score(doc=4683,freq=1.0), product of:
             0.08540735 = queryWeight, product of:
               1.2036412 = boost
               5.081394 = idf(docFreq=749, maxDocs=44421)
               0.013964176 = queryNorm
             0.39698392 = fieldWeight in 4683, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.081394 = idf(docFreq=749, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
         0.050604545 = weight(abstract_txt:values in 4683) [ClassicSimilarity], result of:
           0.050604545 = score(doc=4683,freq=1.0), product of:
             0.11154313 = queryWeight, product of:
               1.3755324 = boost
               5.807065 = idf(docFreq=362, maxDocs=44421)
               0.013964176 = queryNorm
             0.45367694 = fieldWeight in 4683, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.807065 = idf(docFreq=362, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
         0.11743545 = weight(abstract_txt:matrix in 4683) [ClassicSimilarity], result of:
           0.11743545 = score(doc=4683,freq=2.0), product of:
             0.15518126 = queryWeight, product of:
               1.6224414 = boost
               6.849437 = idf(docFreq=127, maxDocs=44421)
               0.013964176 = queryNorm
             0.7567631 = fieldWeight in 4683, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               6.849437 = idf(docFreq=127, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
         0.054919075 = weight(abstract_txt:quality in 4683) [ClassicSimilarity], result of:
           0.054919075 = score(doc=4683,freq=2.0), product of:
             0.10702512 = queryWeight, product of:
               1.650205 = boost
               4.6444306 = idf(docFreq=1160, maxDocs=44421)
               0.013964176 = queryNorm
             0.51314193 = fieldWeight in 4683, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               4.6444306 = idf(docFreq=1160, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
         0.042726625 = weight(abstract_txt:term in 4683) [ClassicSimilarity], result of:
           0.042726625 = score(doc=4683,freq=1.0), product of:
             0.11406331 = queryWeight, product of:
               1.7036015 = boost
               4.794713 = idf(docFreq=998, maxDocs=44421)
               0.013964176 = queryNorm
             0.37458694 = fieldWeight in 4683, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.794713 = idf(docFreq=998, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
         0.10742129 = weight(abstract_txt:clusters in 4683) [ClassicSimilarity], result of:
           0.10742129 = score(doc=4683,freq=1.0), product of:
             0.21089864 = queryWeight, product of:
               2.316498 = boost
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.013964176 = queryNorm
             0.5093503 = fieldWeight in 4683, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               6.519684 = idf(docFreq=177, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
         0.24884228 = weight(abstract_txt:clustering in 4683) [ClassicSimilarity], result of:
           0.24884228 = score(doc=4683,freq=4.0), product of:
             0.2560094 = queryWeight, product of:
               2.947083 = boost
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.013964176 = queryNorm
             0.9720045 = fieldWeight in 4683, product of:
               2.0 = tf(freq=4.0), with freq of:
                 4.0 = termFreq=4.0
               6.2208285 = idf(docFreq=239, maxDocs=44421)
               0.078125 = fieldNorm(doc=4683)
       0.32 = coord(8/25)