What to Evaluate? What can be measured that reflects users' ability to use system? Coverage of information Form of presentation Effort required/ease of use Time and space efficiency 0- Recall Proportion of relevant material actually retrieved Precision Proportion of retrieved material actually relevant3 • What to Evaluate? Effectiveness What can be measured that reflects users’ ability to use system? – Coverage of information – Form of presentation – Effort required/ease of use – Time and space efficiency – Recall ▪ Proportion of relevant material actually retrieved – Precision ▪ Proportion of retrieved material actually relevant