VARIATIONS IN RELEVANCE JUDGMENTS AND THE EVALUATION OF RETRIEVAL PERFORMANCE

The relevance judgments used to evaluate the performance of information retrieval systems are known to vary among judges and to vary under certain conditions extraneous to the relevance relationship between queries and documents. The study reported here investigated the degree to which variations in relevance judgments affect the evaluation of retrieval performance. Four sets of relevance judgments were used to test the retrieval effectiveness of six document representations. In no case was there a noticeable or material difference in retrieval performance due to variations in relevance judgment. Additionally, for each set of relevance judgments, the relative performance of the six different document representations was the same. Reasons why variations in relevance judgments may not affect recall and precision results were examined in further detail.