The Relationship between IR Effectiveness Measures and User Satisfaction

This paper presents an experimental study of users assessing the quality of Google web search results. In particular we look at how users' satisfaction correlates with the effectiveness of Google as quantified by IR measures such as precision and the suite of Cumulative Gain measures (CG, DCG, NDCG). Results indicate strong correlation between users' satisfaction, CG and precision, moderate correlation with DCG, with perhaps surprisingly negligible correlation with NDCG. The reasons for the low correlation with NDCG are examined.