| Similarity |
Page |
Snapshot |
| 154 |
Composite measures Dissatisfaction in the past with methods of measuring effectiveness by a pair of numbers e
...S P R This is simply related to a measure suggested by Borko BK P R 1 More complicated ones are Vickery s measure V can be shown to be a special case of a general measure which will be derived below
...Some single number measures have derivations which can be justified in a rational manner
...The Swets model As early as 1963 Swets [12]showed that the suggested modifications were in fact simply related to an alternative measure already suggested by Swets
...It is interesting that although the Swets model is theoreticallyattractive |
| 10 |
In the past there has been much debate about the validity of evaluations based on relevance judgments provided by erring human beings
...Effectiveness and efficiency Much of the research and development in information retrieval is aimed at improving the effectiveness and efficiency of retrieval
... |
| 158 |
Brookes also gives statistical reasons for preferring S 2 to S 1 which need not concern us here
...Interestingly enough,Robertson [15]showed that S 2 is simply related to the area under the Recall Fallout curve
...The Robertson model the logistic transformation Robertson in collaboration with Teather has developed a model for estimating the probabilities corresponding to recall and fallout [17]... |
| 146 |
There has been much debate in the past as to whether precision and recall are in fact the appropriate quantities to use as measures of effectiveness
...1 the most commonly used pair;2 fairly well understood quantities
...The final question How to evaluate?has a large technical answer
...Before proceeding to the technical details relating to the measurement of effectiveness it is as well to examine more closely the concept of relevance which underlies it
...Relevance Relevance is a subjective notion
... |
| 145 |
automatic and interactive retrieval system?Studies to gauge this are going on but results are hard to interpret
...It should be apparent now that in evaluating an information retrieval system we are mainly concerned with providing data so that users can make a decision as to 1 whether they want such a system social question and 2 whether it will be worth it
...The second question what to evaluate?boils down to what can we measure that will reflect the ability of the system to satisfy the user
...1 The coverage of the collection,that is,the extent to which the system includes relevant matter;2 the time lag,that is,the average interval between the time the search request is made and the time an answer is given;3 the form of presentation of the output;4 the effort involved on the part of the user in obtaining answers to his search requests;5 the recall of the system,that is,the proportion of relevant material actually retrieved in answer to a search request;6 the precision of the system,that is,the proportion of retrieved material that is actually relevant
...It is claimed that 1 4 are readily assessed
... |
