Document (#32994)

Author

Spink, A.
Jansen, B.J.
Blakely, C.
Koshman, S.

Title

¬A study of results overlap and uniqueness among major Web search engines

Source

Information processing and management. 42(2006) no.5, S.1379-1391

Year

2006

Abstract

The performance and capabilities of Web search engines is an important and significant area of research. Millions of people world wide use Web search engines very day. This paper reports the results of a major study examining the overlap among results retrieved by multiple Web search engines for a large set of more than 10,000 queries. Previous smaller studies have discussed a lack of overlap in results returned by Web search engines for the same queries. The goal of the current study was to conduct a large-scale study to measure the overlap of search results on the first result page (both non-sponsored and sponsored) across the four most popular Web search engines, at specific points in time using a large number of queries. The Web search engines included in the study were MSN Search, Google, Yahoo! and Ask Jeeves. Our study then compares these results with the first page results retrieved for the same queries by the metasearch engine Dogpile.com. Two sets of randomly selected user-entered queries, one set was 10,316 queries and the other 12,570 queries, from Infospace's Dogpile.com search engine (the first set was from Dogpile, the second was from across the Infospace Network of search properties were submitted to the four single Web search engines). Findings show that the percent of total results unique to only one of the four Web search engines was 84.9%, shared by two of the three Web search engines was 11.4%, shared by three of the Web search engines was 2.6%, and shared by all four Web search engines was 1.1%. This small degree of overlap shows the significant difference in the way major Web search engines retrieve and rank results in response to given queries. Results point to the value of metasearch engines in Web retrieval to overcome the biases of individual search engines.

Theme

Suchmaschinen
Benutzerstudien

Similar documents (author)

1. Koshman, S.; Spink, A.; Jansen, B.J.: Web searching on the Vivisimo search engine (2006) 5.29

   5.2867017 = sum of:
     5.2867017 = sum of:
       1.2450736 = weight(author_txt:spink in 216) [ClassicSimilarity], result of:
         1.2450736 = score(doc=216,freq=1.0), product of:
           0.4523318 = queryWeight, product of:
             7.3401785 = idf(docFreq=77, maxDocs=44218)
             0.061624087 = queryNorm
           2.7525668 = fieldWeight in 216, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             7.3401785 = idf(docFreq=77, maxDocs=44218)
             0.375 = fieldNorm(doc=216)
       1.4314582 = weight(author_txt:jansen in 216) [ClassicSimilarity], result of:
         1.4314582 = score(doc=216,freq=1.0), product of:
           0.49641654 = queryWeight, product of:
             1.0475978 = boost
             7.689554 = idf(docFreq=54, maxDocs=44218)
             0.061624087 = queryNorm
           2.8835828 = fieldWeight in 216, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             7.689554 = idf(docFreq=54, maxDocs=44218)
             0.375 = fieldNorm(doc=216)
       2.61017 = weight(author_txt:koshman in 216) [ClassicSimilarity], result of:
         2.61017 = score(doc=216,freq=1.0), product of:
           0.7409228 = queryWeight, product of:
             1.2798465 = boost
             9.394302 = idf(docFreq=9, maxDocs=44218)
             0.061624087 = queryNorm
           3.5228634 = fieldWeight in 216, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             9.394302 = idf(docFreq=9, maxDocs=44218)
             0.375 = fieldNorm(doc=216)
   

2. Jansen, B.J.; Spink, A.; Koshman, S.: Web searcher interaction with the Dogpile.com metasearch engine (2007) 5.29

   5.2867017 = sum of:
     5.2867017 = sum of:
       1.2450736 = weight(author_txt:spink in 270) [ClassicSimilarity], result of:
         1.2450736 = score(doc=270,freq=1.0), product of:
           0.4523318 = queryWeight, product of:
             7.3401785 = idf(docFreq=77, maxDocs=44218)
             0.061624087 = queryNorm
           2.7525668 = fieldWeight in 270, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             7.3401785 = idf(docFreq=77, maxDocs=44218)
             0.375 = fieldNorm(doc=270)
       1.4314582 = weight(author_txt:jansen in 270) [ClassicSimilarity], result of:
         1.4314582 = score(doc=270,freq=1.0), product of:
           0.49641654 = queryWeight, product of:
             1.0475978 = boost
             7.689554 = idf(docFreq=54, maxDocs=44218)
             0.061624087 = queryNorm
           2.8835828 = fieldWeight in 270, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             7.689554 = idf(docFreq=54, maxDocs=44218)
             0.375 = fieldNorm(doc=270)
       2.61017 = weight(author_txt:koshman in 270) [ClassicSimilarity], result of:
         2.61017 = score(doc=270,freq=1.0), product of:
           0.7409228 = queryWeight, product of:
             1.2798465 = boost
             9.394302 = idf(docFreq=9, maxDocs=44218)
             0.061624087 = queryNorm
           3.5228634 = fieldWeight in 270, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             9.394302 = idf(docFreq=9, maxDocs=44218)
             0.375 = fieldNorm(doc=270)
   

3. Jansen, B.J.; Spink, A.; Blakely, C.; Koshman, S.: Defining a session on Web search engines (2007) 4.41

   4.4055843 = sum of:
     4.4055843 = sum of:
       1.0375613 = weight(author_txt:spink in 285) [ClassicSimilarity], result of:
         1.0375613 = score(doc=285,freq=1.0), product of:
           0.4523318 = queryWeight, product of:
             7.3401785 = idf(docFreq=77, maxDocs=44218)
             0.061624087 = queryNorm
           2.2938058 = fieldWeight in 285, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             7.3401785 = idf(docFreq=77, maxDocs=44218)
             0.3125 = fieldNorm(doc=285)
       1.1928818 = weight(author_txt:jansen in 285) [ClassicSimilarity], result of:
         1.1928818 = score(doc=285,freq=1.0), product of:
           0.49641654 = queryWeight, product of:
             1.0475978 = boost
             7.689554 = idf(docFreq=54, maxDocs=44218)
             0.061624087 = queryNorm
           2.4029856 = fieldWeight in 285, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             7.689554 = idf(docFreq=54, maxDocs=44218)
             0.3125 = fieldNorm(doc=285)
       2.1751416 = weight(author_txt:koshman in 285) [ClassicSimilarity], result of:
         2.1751416 = score(doc=285,freq=1.0), product of:
           0.7409228 = queryWeight, product of:
             1.2798465 = boost
             9.394302 = idf(docFreq=9, maxDocs=44218)
             0.061624087 = queryNorm
           2.9357195 = fieldWeight in 285, product of:
             1.0 = tf(freq=1.0), with freq of:
               1.0 = termFreq=1.0
             9.394302 = idf(docFreq=9, maxDocs=44218)
             0.3125 = fieldNorm(doc=285)
   

4. Spink, A.; Park, M.; Koshman, S.: Factors affecting assigned information problem ordering during Web search : an exploratory study (2006) 2.57

   2.5701623 = sum of:
     2.5701623 = product of:
       3.8552434 = sum of:
         1.2450736 = weight(author_txt:spink in 991) [ClassicSimilarity], result of:
           1.2450736 = score(doc=991,freq=1.0), product of:
             0.4523318 = queryWeight, product of:
               7.3401785 = idf(docFreq=77, maxDocs=44218)
               0.061624087 = queryNorm
             2.7525668 = fieldWeight in 991, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               7.3401785 = idf(docFreq=77, maxDocs=44218)
               0.375 = fieldNorm(doc=991)
         2.61017 = weight(author_txt:koshman in 991) [ClassicSimilarity], result of:
           2.61017 = score(doc=991,freq=1.0), product of:
             0.7409228 = queryWeight, product of:
               1.2798465 = boost
               9.394302 = idf(docFreq=9, maxDocs=44218)
               0.061624087 = queryNorm
             3.5228634 = fieldWeight in 991, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               9.394302 = idf(docFreq=9, maxDocs=44218)
               0.375 = fieldNorm(doc=991)
       0.6666667 = coord(2/3)
   

5. Jansen, B.J.; Spink, A.: How are we searching the World Wide Web? : A comparison of nine search engine transaction logs (2006) 2.38

   2.3791394 = sum of:
     2.3791394 = product of:
       3.568709 = sum of:
         1.6600981 = weight(author_txt:spink in 968) [ClassicSimilarity], result of:
           1.6600981 = score(doc=968,freq=1.0), product of:
             0.4523318 = queryWeight, product of:
               7.3401785 = idf(docFreq=77, maxDocs=44218)
               0.061624087 = queryNorm
             3.6700892 = fieldWeight in 968, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               7.3401785 = idf(docFreq=77, maxDocs=44218)
               0.5 = fieldNorm(doc=968)
         1.9086109 = weight(author_txt:jansen in 968) [ClassicSimilarity], result of:
           1.9086109 = score(doc=968,freq=1.0), product of:
             0.49641654 = queryWeight, product of:
               1.0475978 = boost
               7.689554 = idf(docFreq=54, maxDocs=44218)
               0.061624087 = queryNorm
             3.844777 = fieldWeight in 968, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               7.689554 = idf(docFreq=54, maxDocs=44218)
               0.5 = fieldNorm(doc=968)
       0.6666667 = coord(2/3)
   

Similar documents (content)

1. Bar-Ilan, J.; Keenoy, K.; Yaari, E.; Levene, M.: User rankings of search engine results (2007) 0.63

   0.6309797 = sum of:
     0.6309797 = product of:
       1.1267495 = sum of:
         0.0057969075 = weight(abstract_txt:from in 470) [ClassicSimilarity], result of:
           0.0057969075 = score(doc=470,freq=1.0), product of:
             0.033558052 = queryWeight, product of:
               2.7638826 = idf(docFreq=7577, maxDocs=44218)
               0.012141635 = queryNorm
             0.17274266 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               2.7638826 = idf(docFreq=7577, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.015764844 = weight(abstract_txt:three in 470) [ClassicSimilarity], result of:
           0.015764844 = score(doc=470,freq=1.0), product of:
             0.05711654 = queryWeight, product of:
               1.0652142 = boost
               4.41619 = idf(docFreq=1451, maxDocs=44218)
               0.012141635 = queryNorm
             0.27601188 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.41619 = idf(docFreq=1451, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.019509092 = weight(abstract_txt:same in 470) [ClassicSimilarity], result of:
           0.019509092 = score(doc=470,freq=1.0), product of:
             0.0658355 = queryWeight, product of:
               1.1436313 = boost
               4.7412944 = idf(docFreq=1048, maxDocs=44218)
               0.012141635 = queryNorm
             0.2963309 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.7412944 = idf(docFreq=1048, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.030908639 = weight(abstract_txt:engine in 470) [ClassicSimilarity], result of:
           0.030908639 = score(doc=470,freq=1.0), product of:
             0.089472316 = queryWeight, product of:
               1.3332155 = boost
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.012141635 = queryNorm
             0.34545478 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.04813891 = weight(abstract_txt:retrieved in 470) [ClassicSimilarity], result of:
           0.04813891 = score(doc=470,freq=2.0), product of:
             0.09541638 = queryWeight, product of:
               1.3767892 = boost
               5.707926 = idf(docFreq=398, maxDocs=44218)
               0.012141635 = queryNorm
             0.5045141 = fieldWeight in 470, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               5.707926 = idf(docFreq=398, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.019880453 = weight(abstract_txt:first in 470) [ClassicSimilarity], result of:
           0.019880453 = score(doc=470,freq=1.0), product of:
             0.07631619 = queryWeight, product of:
               1.5080299 = boost
               4.168018 = idf(docFreq=1860, maxDocs=44218)
               0.012141635 = queryNorm
             0.26050112 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.168018 = idf(docFreq=1860, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.024261314 = weight(abstract_txt:large in 470) [ClassicSimilarity], result of:
           0.024261314 = score(doc=470,freq=1.0), product of:
             0.08715161 = queryWeight, product of:
               1.6115334 = boost
               4.454089 = idf(docFreq=1397, maxDocs=44218)
               0.012141635 = queryNorm
             0.27838057 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.454089 = idf(docFreq=1397, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.02771881 = weight(abstract_txt:major in 470) [ClassicSimilarity], result of:
           0.02771881 = score(doc=470,freq=1.0), product of:
             0.09524647 = queryWeight, product of:
               1.6847135 = boost
               4.6563506 = idf(docFreq=1141, maxDocs=44218)
               0.012141635 = queryNorm
             0.2910219 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.6563506 = idf(docFreq=1141, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.02203916 = weight(abstract_txt:study in 470) [ClassicSimilarity], result of:
           0.02203916 = score(doc=470,freq=1.0), product of:
             0.102992564 = queryWeight, product of:
               2.4775336 = boost
               3.423806 = idf(docFreq=3916, maxDocs=44218)
               0.012141635 = queryNorm
             0.21398787 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               3.423806 = idf(docFreq=3916, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.051210057 = weight(abstract_txt:four in 470) [ClassicSimilarity], result of:
           0.051210057 = score(doc=470,freq=1.0), product of:
             0.15783946 = queryWeight, product of:
               2.5042562 = boost
               5.191103 = idf(docFreq=668, maxDocs=44218)
               0.012141635 = queryNorm
             0.32444394 = fieldWeight in 470, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.191103 = idf(docFreq=668, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.086426236 = weight(abstract_txt:results in 470) [ClassicSimilarity], result of:
           0.086426236 = score(doc=470,freq=5.0), product of:
             0.1775821 = queryWeight, product of:
               4.199916 = boost
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.012141635 = queryNorm
             0.48668328 = fieldWeight in 470, product of:
               2.236068 = tf(freq=5.0), with freq of:
                 5.0 = termFreq=5.0
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.13788381 = weight(abstract_txt:queries in 470) [ClassicSimilarity], result of:
           0.13788381 = score(doc=470,freq=2.0), product of:
             0.3054834 = queryWeight, product of:
               4.9269686 = boost
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.012141635 = queryNorm
             0.4513627 = fieldWeight in 470, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.2280781 = weight(abstract_txt:search in 470) [ClassicSimilarity], result of:
           0.2280781 = score(doc=470,freq=8.0), product of:
             0.3527026 = queryWeight, product of:
               7.9411163 = boost
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.012141635 = queryNorm
             0.6466584 = fieldWeight in 470, product of:
               2.828427 = tf(freq=8.0), with freq of:
                 8.0 = termFreq=8.0
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
         0.40913326 = weight(abstract_txt:engines in 470) [ClassicSimilarity], result of:
           0.40913326 = score(doc=470,freq=4.0), product of:
             0.61737025 = queryWeight, product of:
               9.590902 = boost
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.012141635 = queryNorm
             0.6627032 = fieldWeight in 470, product of:
               2.0 = tf(freq=4.0), with freq of:
                 4.0 = termFreq=4.0
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.0625 = fieldNorm(doc=470)
       0.56 = coord(14/25)
   

2. Bar-Ilan, J.: Comparing rankings of search results on the Web (2005) 0.58

   0.57656205 = sum of:
     0.57656205 = product of:
       1.3103683 = sum of:
         0.0057969075 = weight(abstract_txt:from in 1068) [ClassicSimilarity], result of:
           0.0057969075 = score(doc=1068,freq=1.0), product of:
             0.033558052 = queryWeight, product of:
               2.7638826 = idf(docFreq=7577, maxDocs=44218)
               0.012141635 = queryNorm
             0.17274266 = fieldWeight in 1068, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               2.7638826 = idf(docFreq=7577, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.030908639 = weight(abstract_txt:engine in 1068) [ClassicSimilarity], result of:
           0.030908639 = score(doc=1068,freq=1.0), product of:
             0.089472316 = queryWeight, product of:
               1.3332155 = boost
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.012141635 = queryNorm
             0.34545478 = fieldWeight in 1068, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.034039352 = weight(abstract_txt:retrieved in 1068) [ClassicSimilarity], result of:
           0.034039352 = score(doc=1068,freq=1.0), product of:
             0.09541638 = queryWeight, product of:
               1.3767892 = boost
               5.707926 = idf(docFreq=398, maxDocs=44218)
               0.012141635 = queryNorm
             0.35674536 = fieldWeight in 1068, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.707926 = idf(docFreq=398, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.03431068 = weight(abstract_txt:large in 1068) [ClassicSimilarity], result of:
           0.03431068 = score(doc=1068,freq=2.0), product of:
             0.08715161 = queryWeight, product of:
               1.6115334 = boost
               4.454089 = idf(docFreq=1397, maxDocs=44218)
               0.012141635 = queryNorm
             0.39368957 = fieldWeight in 1068, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               4.454089 = idf(docFreq=1397, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.02203916 = weight(abstract_txt:study in 1068) [ClassicSimilarity], result of:
           0.02203916 = score(doc=1068,freq=1.0), product of:
             0.102992564 = queryWeight, product of:
               2.4775336 = boost
               3.423806 = idf(docFreq=3916, maxDocs=44218)
               0.012141635 = queryNorm
             0.21398787 = fieldWeight in 1068, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               3.423806 = idf(docFreq=3916, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.051210057 = weight(abstract_txt:four in 1068) [ClassicSimilarity], result of:
           0.051210057 = score(doc=1068,freq=1.0), product of:
             0.15783946 = queryWeight, product of:
               2.5042562 = boost
               5.191103 = idf(docFreq=668, maxDocs=44218)
               0.012141635 = queryNorm
             0.32444394 = fieldWeight in 1068, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.191103 = idf(docFreq=668, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.15317346 = weight(abstract_txt:overlap in 1068) [ClassicSimilarity], result of:
           0.15317346 = score(doc=1068,freq=1.0), product of:
             0.35296997 = queryWeight, product of:
               4.186922 = boost
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.012141635 = queryNorm
             0.43395606 = fieldWeight in 1068, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.086426236 = weight(abstract_txt:results in 1068) [ClassicSimilarity], result of:
           0.086426236 = score(doc=1068,freq=5.0), product of:
             0.1775821 = queryWeight, product of:
               4.199916 = boost
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.012141635 = queryNorm
             0.48668328 = fieldWeight in 1068, product of:
               2.236068 = tf(freq=5.0), with freq of:
                 5.0 = termFreq=5.0
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.13788381 = weight(abstract_txt:queries in 1068) [ClassicSimilarity], result of:
           0.13788381 = score(doc=1068,freq=2.0), product of:
             0.3054834 = queryWeight, product of:
               4.9269686 = boost
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.012141635 = queryNorm
             0.4513627 = fieldWeight in 1068, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.21334752 = weight(abstract_txt:search in 1068) [ClassicSimilarity], result of:
           0.21334752 = score(doc=1068,freq=7.0), product of:
             0.3527026 = queryWeight, product of:
               7.9411163 = boost
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.012141635 = queryNorm
             0.60489357 = fieldWeight in 1068, product of:
               2.6457512 = tf(freq=7.0), with freq of:
                 7.0 = termFreq=7.0
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
         0.5412324 = weight(abstract_txt:engines in 1068) [ClassicSimilarity], result of:
           0.5412324 = score(doc=1068,freq=7.0), product of:
             0.61737025 = queryWeight, product of:
               9.590902 = boost
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.012141635 = queryNorm
             0.87667394 = fieldWeight in 1068, product of:
               2.6457512 = tf(freq=7.0), with freq of:
                 7.0 = termFreq=7.0
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.0625 = fieldNorm(doc=1068)
       0.44 = coord(11/25)
   

3. Bilal, D.: Web search engines for children : a comparative study and performance evaluation of Yahooligans!, AskJeeves for Kids, and Super Snooper (1999) 0.51

   0.5122901 = sum of:
     0.5122901 = product of:
       1.1642958 = sum of:
         0.008198065 = weight(abstract_txt:from in 6544) [ClassicSimilarity], result of:
           0.008198065 = score(doc=6544,freq=2.0), product of:
             0.033558052 = queryWeight, product of:
               2.7638826 = idf(docFreq=7577, maxDocs=44218)
               0.012141635 = queryNorm
             0.24429502 = fieldWeight in 6544, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               2.7638826 = idf(docFreq=7577, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.022294855 = weight(abstract_txt:three in 6544) [ClassicSimilarity], result of:
           0.022294855 = score(doc=6544,freq=2.0), product of:
             0.05711654 = queryWeight, product of:
               1.0652142 = boost
               4.41619 = idf(docFreq=1451, maxDocs=44218)
               0.012141635 = queryNorm
             0.39033973 = fieldWeight in 6544, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               4.41619 = idf(docFreq=1451, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.1645542 = weight(abstract_txt:jeeves in 6544) [ClassicSimilarity], result of:
           0.1645542 = score(doc=6544,freq=5.0), product of:
             0.12662168 = queryWeight, product of:
               1.121489 = boost
               9.298992 = idf(docFreq=10, maxDocs=44218)
               0.012141635 = queryNorm
             1.2995737 = fieldWeight in 6544, product of:
               2.236068 = tf(freq=5.0), with freq of:
                 5.0 = termFreq=5.0
               9.298992 = idf(docFreq=10, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.043711416 = weight(abstract_txt:engine in 6544) [ClassicSimilarity], result of:
           0.043711416 = score(doc=6544,freq=2.0), product of:
             0.089472316 = queryWeight, product of:
               1.3332155 = boost
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.012141635 = queryNorm
             0.48854682 = fieldWeight in 6544, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.034039352 = weight(abstract_txt:retrieved in 6544) [ClassicSimilarity], result of:
           0.034039352 = score(doc=6544,freq=1.0), product of:
             0.09541638 = queryWeight, product of:
               1.3767892 = boost
               5.707926 = idf(docFreq=398, maxDocs=44218)
               0.012141635 = queryNorm
             0.35674536 = fieldWeight in 6544, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.707926 = idf(docFreq=398, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.02203916 = weight(abstract_txt:study in 6544) [ClassicSimilarity], result of:
           0.02203916 = score(doc=6544,freq=1.0), product of:
             0.102992564 = queryWeight, product of:
               2.4775336 = boost
               3.423806 = idf(docFreq=3916, maxDocs=44218)
               0.012141635 = queryNorm
             0.21398787 = fieldWeight in 6544, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               3.423806 = idf(docFreq=3916, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.15317346 = weight(abstract_txt:overlap in 6544) [ClassicSimilarity], result of:
           0.15317346 = score(doc=6544,freq=1.0), product of:
             0.35296997 = queryWeight, product of:
               4.186922 = boost
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.012141635 = queryNorm
             0.43395606 = fieldWeight in 6544, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.06694548 = weight(abstract_txt:results in 6544) [ClassicSimilarity], result of:
           0.06694548 = score(doc=6544,freq=3.0), product of:
             0.1775821 = queryWeight, product of:
               4.199916 = boost
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.012141635 = queryNorm
             0.37698326 = fieldWeight in 6544, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.09749858 = weight(abstract_txt:queries in 6544) [ClassicSimilarity], result of:
           0.09749858 = score(doc=6544,freq=1.0), product of:
             0.3054834 = queryWeight, product of:
               4.9269686 = boost
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.012141635 = queryNorm
             0.31916162 = fieldWeight in 6544, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.19752143 = weight(abstract_txt:search in 6544) [ClassicSimilarity], result of:
           0.19752143 = score(doc=6544,freq=6.0), product of:
             0.3527026 = queryWeight, product of:
               7.9411163 = boost
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.012141635 = queryNorm
             0.56002265 = fieldWeight in 6544, product of:
               2.4494898 = tf(freq=6.0), with freq of:
                 6.0 = termFreq=6.0
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
         0.35431978 = weight(abstract_txt:engines in 6544) [ClassicSimilarity], result of:
           0.35431978 = score(doc=6544,freq=3.0), product of:
             0.61737025 = queryWeight, product of:
               9.590902 = boost
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.012141635 = queryNorm
             0.5739178 = fieldWeight in 6544, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.0625 = fieldNorm(doc=6544)
       0.44 = coord(11/25)
   

4. Bar-Ilan, J.; Levene, M.; Mat-Hassan, M.: Methods for evaluating dynamic changes in search engine rankings : a case study (2006) 0.49

   0.49331608 = sum of:
     0.49331608 = product of:
       1.2332902 = sum of:
         0.023892319 = weight(abstract_txt:three in 616) [ClassicSimilarity], result of:
           0.023892319 = score(doc=616,freq=3.0), product of:
             0.05711654 = queryWeight, product of:
               1.0652142 = boost
               4.41619 = idf(docFreq=1451, maxDocs=44218)
               0.012141635 = queryNorm
             0.41830826 = fieldWeight in 616, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               4.41619 = idf(docFreq=1451, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.03824749 = weight(abstract_txt:engine in 616) [ClassicSimilarity], result of:
           0.03824749 = score(doc=616,freq=2.0), product of:
             0.089472316 = queryWeight, product of:
               1.3332155 = boost
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.012141635 = queryNorm
             0.42747846 = fieldWeight in 616, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.034533106 = weight(abstract_txt:page in 616) [ClassicSimilarity], result of:
           0.034533106 = score(doc=616,freq=1.0), product of:
             0.10530617 = queryWeight, product of:
               1.4463817 = boost
               5.9964437 = idf(docFreq=298, maxDocs=44218)
               0.012141635 = queryNorm
             0.3279305 = fieldWeight in 616, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               5.9964437 = idf(docFreq=298, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.017395396 = weight(abstract_txt:first in 616) [ClassicSimilarity], result of:
           0.017395396 = score(doc=616,freq=1.0), product of:
             0.07631619 = queryWeight, product of:
               1.5080299 = boost
               4.168018 = idf(docFreq=1860, maxDocs=44218)
               0.012141635 = queryNorm
             0.22793847 = fieldWeight in 616, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.168018 = idf(docFreq=1860, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.034300275 = weight(abstract_txt:major in 616) [ClassicSimilarity], result of:
           0.034300275 = score(doc=616,freq=2.0), product of:
             0.09524647 = queryWeight, product of:
               1.6847135 = boost
               4.6563506 = idf(docFreq=1141, maxDocs=44218)
               0.012141635 = queryNorm
             0.36012122 = fieldWeight in 616, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               4.6563506 = idf(docFreq=1141, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.18954247 = weight(abstract_txt:overlap in 616) [ClassicSimilarity], result of:
           0.18954247 = score(doc=616,freq=2.0), product of:
             0.35296997 = queryWeight, product of:
               4.186922 = boost
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.012141635 = queryNorm
             0.5369932 = fieldWeight in 616, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.08947829 = weight(abstract_txt:results in 616) [ClassicSimilarity], result of:
           0.08947829 = score(doc=616,freq=7.0), product of:
             0.1775821 = queryWeight, product of:
               4.199916 = boost
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.012141635 = queryNorm
             0.50387 = fieldWeight in 616, product of:
               2.6457512 = tf(freq=7.0), with freq of:
                 7.0 = termFreq=7.0
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.12064834 = weight(abstract_txt:queries in 616) [ClassicSimilarity], result of:
           0.12064834 = score(doc=616,freq=2.0), product of:
             0.3054834 = queryWeight, product of:
               4.9269686 = boost
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.012141635 = queryNorm
             0.39494237 = fieldWeight in 616, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               5.106586 = idf(docFreq=727, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.21167418 = weight(abstract_txt:search in 616) [ClassicSimilarity], result of:
           0.21167418 = score(doc=616,freq=9.0), product of:
             0.3527026 = queryWeight, product of:
               7.9411163 = boost
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.012141635 = queryNorm
             0.6001492 = fieldWeight in 616, product of:
               3.0 = tf(freq=9.0), with freq of:
                 9.0 = termFreq=9.0
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
         0.47357836 = weight(abstract_txt:engines in 616) [ClassicSimilarity], result of:
           0.47357836 = score(doc=616,freq=7.0), product of:
             0.61737025 = queryWeight, product of:
               9.590902 = boost
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.012141635 = queryNorm
             0.7670897 = fieldWeight in 616, product of:
               2.6457512 = tf(freq=7.0), with freq of:
                 7.0 = termFreq=7.0
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.0546875 = fieldNorm(doc=616)
       0.4 = coord(10/25)
   

5. Feldman, S.: Web search services in 1998 : trends and challenges (1998) 0.48

   0.48348007 = sum of:
     0.48348007 = product of:
       1.5108752 = sum of:
         0.11038631 = weight(abstract_txt:jeeves in 5215) [ClassicSimilarity], result of:
           0.11038631 = score(doc=5215,freq=1.0), product of:
             0.12662168 = queryWeight, product of:
               1.121489 = boost
               9.298992 = idf(docFreq=10, maxDocs=44218)
               0.012141635 = queryNorm
             0.8717805 = fieldWeight in 5215, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               9.298992 = idf(docFreq=10, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
         0.06556712 = weight(abstract_txt:engine in 5215) [ClassicSimilarity], result of:
           0.06556712 = score(doc=5215,freq=2.0), product of:
             0.089472316 = queryWeight, product of:
               1.3332155 = boost
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.012141635 = queryNorm
             0.7328202 = fieldWeight in 5215, product of:
               1.4142135 = tf(freq=2.0), with freq of:
                 2.0 = termFreq=2.0
               5.5272765 = idf(docFreq=477, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
         0.041578215 = weight(abstract_txt:major in 5215) [ClassicSimilarity], result of:
           0.041578215 = score(doc=5215,freq=1.0), product of:
             0.09524647 = queryWeight, product of:
               1.6847135 = boost
               4.6563506 = idf(docFreq=1141, maxDocs=44218)
               0.012141635 = queryNorm
             0.43653286 = fieldWeight in 5215, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               4.6563506 = idf(docFreq=1141, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
         0.17784517 = weight(abstract_txt:metasearch in 5215) [ClassicSimilarity], result of:
           0.17784517 = score(doc=5215,freq=1.0), product of:
             0.21924816 = queryWeight, product of:
               2.0870073 = boost
               8.652365 = idf(docFreq=20, maxDocs=44218)
               0.012141635 = queryNorm
             0.8111592 = fieldWeight in 5215, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               8.652365 = idf(docFreq=20, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
         0.2297602 = weight(abstract_txt:overlap in 5215) [ClassicSimilarity], result of:
           0.2297602 = score(doc=5215,freq=1.0), product of:
             0.35296997 = queryWeight, product of:
               4.186922 = boost
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.012141635 = queryNorm
             0.6509341 = fieldWeight in 5215, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               6.943297 = idf(docFreq=115, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
         0.057976484 = weight(abstract_txt:results in 5215) [ClassicSimilarity], result of:
           0.057976484 = score(doc=5215,freq=1.0), product of:
             0.1775821 = queryWeight, product of:
               4.199916 = boost
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.012141635 = queryNorm
             0.32647708 = fieldWeight in 5215, product of:
               1.0 = tf(freq=1.0), with freq of:
                 1.0 = termFreq=1.0
               3.482422 = idf(docFreq=3693, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
         0.29628217 = weight(abstract_txt:search in 5215) [ClassicSimilarity], result of:
           0.29628217 = score(doc=5215,freq=6.0), product of:
             0.3527026 = queryWeight, product of:
               7.9411163 = boost
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.012141635 = queryNorm
             0.840034 = fieldWeight in 5215, product of:
               2.4494898 = tf(freq=6.0), with freq of:
                 6.0 = termFreq=6.0
               3.6580524 = idf(docFreq=3098, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
         0.53147966 = weight(abstract_txt:engines in 5215) [ClassicSimilarity], result of:
           0.53147966 = score(doc=5215,freq=3.0), product of:
             0.61737025 = queryWeight, product of:
               9.590902 = boost
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.012141635 = queryNorm
             0.8608767 = fieldWeight in 5215, product of:
               1.7320508 = tf(freq=3.0), with freq of:
                 3.0 = termFreq=3.0
               5.3016257 = idf(docFreq=598, maxDocs=44218)
               0.09375 = fieldNorm(doc=5215)
       0.32 = coord(8/25)