User Modeling and Recommender Systems: evaluation and interfaces Adolfo Ruiz Calleja 18/10/2014

Index 2 Some administrative staff Evaluation of recommender systems Interfaces for recommender systems

Index 3 Some administrative staff – Administrative DLs – Final project DLs Evaluation of recommender systems Interfaces for recommender systems

Administrative DLs 4 Lecturers in agreement with the study group, must set two exams times. I open those times in the Study Information System (ÕIS). Student must register themselves on one of these times. The responsible member of teaching staff has 10 working days to enter the results of exams/assessments on to the Study Information System. A student who receives a negative result have right to participate on the re- examination once until the end of Spring semesters intermediate week (March 22, 2015). Lecturer have right to choose, when he/she will conduct the re-exam. If student doesn't pass the course by the end of next semester intermediate week, then he/she must re-take the whole course. How to organize exam/assessment/re-examination? – Lecturer will set a exam/assessment/re-examination times and informs me – I will open those times – Student registers (registration is possible until 24h before the exam) – ~24h before exam - lecturer contact with me and asks the list of participants – Exam/assessment/re-examination will take place. NB! Lecturers must not allow to the exam/assessment/re-examination students who are not registered! – I enter the result. NB! System doesn't allow me to enter the results to students who haven't registered to the exam/assessment/re-examination!

5 Official evaluation dates: Dec. 20 th and 21 st Projects should be reviewed by 1 st of January Re-examination: Feb. 15 th – Those who fail/not-presented  send the project – Those who want better grades  send new version of the project + send answer to my review Administrative DLs

6 October, 18th: Projects are proposed by the students. October, 19th: Students start working on their projects. October, 23rd: I can still be asked about the project topics. December, 1st: First complete draft of the projects December, 8th: Each student should have peer-reviewed at least two projects of his colleagues. December, 13 th and 14th: Projects are presented December, 21 st : Projects are finished January, 1st: Projects are reviewed. Final project DLs

Index 7 Some administrative staff Evaluation of recommender systems – General comment – Common metrics – Data gathering techniques Interfaces for recommender systems

General comment 8 What do you want to evaluate? What characteristics are relevant for this evaluation? What metrics are relevant? Which techniques can be employed to gather data?

Common metrics (accuracy) 9 Relevant Retrieved b ac d

Common metrics (accuracy) 10 Precision Recall Fall-out F-metrics Mean Absolute Error, Mean Square Error… …and many others

Common metrics (beyond accuracy) 11 Coverage Learning Rate Serendipity Confidence User reactions – Explicit (ask) vs. Implicit (log) – Outcome vs. Process – Short-term vs. Long-term

Data gathering techniques 12 Feature analysis Test the system with synthetic data Test the system with developers or experts Test the system with users – Laboratory vs. Field studies – Formal experiment vs. Analysis of user behavior

13 Ask a question I want... SQL Select results 5 results. Do they satisfy you? Dataset Wizard of Oz Algorithm

Index 14 Some administrative staff Evaluation of recommender systems Interfaces for recommender systems – Recommendations – Explanations – Interactions

Recommendations 15 Top Item Top N-Items Predicted ratings for each item Structured overview (divided into categories)

Explanations: Benefits 16 Transparency  explain how the system works Scrutability  allow users to say that the system is wrong Trust  increase user’s confidence Effectiveness  Help users to make decissions Persuasiveness  Convince users to take an item Efficiency  Help users to make faster decissions Satisfaction  Increse the easy of use or the user enjoyenment

Explanations: Guideline 17 Consider the benefits that you would like to obtain from the recommendations How you present explanations affect the interaction model The type of recommendations provided have an impact on the underlying algorithm Be careful: the evaluation of explanations is related to the underlying algorithm

Interactions: What does the user need to do? 18 Nothing Specify his requirements – Maybe we can ask him to change the requirements Explicitly ask for recommendations – More like this – More later – No more like this – Surprise me! – “I´m feeling lucky”

User Modeling and Recommender Systems: evaluation and interfaces Adolfo Ruiz Calleja 18/10/2014