19 Oct 2004
CS 5244: Library Evaluation
25
Evaluation Metrics
ˇPrecision = Positive Predictive Value
l“ratio of the number of relevant documents retrieved over the total number of documents retrieved”
lhow much extra stuff did you get?
ˇRecall = Sensitivity
l“ratio of relevant documents retrieved for a given query over the number of relevant documents for that query in the database”
lhow much did you miss?
TP
TP+FP
TP
TP+FN