| Similarity |
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Snapshot |
| 54 |
the hierarchy one can identify a set of classes,and as one moves up the hierarchy the classes at the lower levels are nested in the classes at the higher levels
...It is now a simple matter to define single link in terms of these graphs;at any level a single link cluster is precisely the set of vertices of a connected component of the graph at that level
...corresponding clusters at those levels
... |
| 55 |
This description immediately leads to an inefficient algorithm for the generation of single link classes
... |
| 60 |
differences in the scale and in the use to which a classification structure is to be put
...In the case of scale,the size of the problem in IR is invariably such that for cluster methods based on similarity matrices it becomes impossible to store the entire similarity matrix,let alone allow random access to its elements
...When a classification is to be used in IR,it affects the design of the algorithm to the extent that a classification will be represented by a file structure which is 1 easily updated;2 easily searched;and 3 reasonably compact
...Only 3 needs some further comment
...Conclusion Let me briefly summarise the logical structure of this chapter
...This chapter ended on a rather practical note
... |
| 134 |
which from a computational point of view would simplify things enormously
...An alternative way of using the dependence tree Association Hypothesis Some of the arguments advanced in the previous section can be construed as implying that the only dependence tree we have enough information to construct is the one on the entire document collection
...The basic idea underlying term clustering was explained in Chapter 2
...If an index term is good at discriminating relevant from non relevantdocuments then any closely associated index term is also likely to begood at this
... |
| 140 |
derives from the work of Yu and his collaborators [28,29]...According to Doyle [32]p
...The model in this chapter also connects with two other ideas in earlier research
...or in words,for any document the probability of relevance is inversely proportional the probability with which it will occur on a random basis
... |
