1. Tactics Used When Searching for Digital Videos Barbara M. Wildemuth Jung Sun Oh Gary Marchionini University of North Carolina at Chapel Hill

2. The research question  Which search tactics do people use when they search for digital videos ?

3. Some vocabulary

4. What do we know already ? The most frequently - used search move is to add terms / concepts, to decrease the search results ( Vakkari et al., 2003; Wildemuth, 2004) 22-33% of Web queries are modifications of a previous query ( Jansen et al., 2000, 2009; Spink et al., 2000) People do change their search tactics when presented with different capabilities ( Kules & Shneiderman, 2008)

5. Sample of participants 36 graduate and undergraduate students from 17 different departments 75% watch videos daily or weekly 36% search for videos daily or weekly

6. The database of videos

7. Data collection procedures Demographic questionnaire Conduct searches ( x 4) –Assigned search tasks –Conduct search and make relevance judgments Transaction logs captured during searches

8. Search tasks Example : Imagine that you are an emergency response officer in California and that you are developing an online tutorial on how to respond to an earthquake. You would like to illustrate the tutorial with video showing the damage that can be caused by an earthquake. ConcreteAbstract For viewingRole of rivers, recent videosAmerica’s obsession with cars, 1930-1950 For productionEarthquake damageAny topic, for montage of early, popular videos

9. Data analysis Coding the search moves –Using codes based on Shute & Smith (1993) and Bates (1979) – 1545 moves ; ~11 moves per search Maximal repeating patterns ( MRP ) analysis to identify frequently - used tactics ( Siochi & Ehrich, 1991) Combine similar MRPs to identify tactics

10. Search task : Imagine that you are a history professor, teaching a course on the history of technology in the U. S. You want to find some footage that illustrates America ’ s growing obsession with cars / automobiles between 1930 and 1950. ( abstract ; for viewing ) Search conducted by participant 40: Term: automobile + Term: 1930-1950 Display automobile  car Display car  car culture Display car culture  car culture advertising Display Search task  Queries

11. Search conducted by participant 40: Term: automobile + Term: 1930-1950 Display automobile  car Display car  car culture Display car culture  car culture advertising Display Coding of participant 40’ s search : New search Add concept Display Replace term Display Add concept Display Add concept Display Queries coded

12. #125 Coding of participant 40’ s search : New search Add concept Display Replace term Display Add concept Display Add concept Display MRP identification

13. MRPs  Tactic

14. Tactics B, C, F

15. Tactics K, L, M

16. Key findings A small number of different moves predominate : New search, Add concept, Delete concept, Display These moves are used to make up a wide variety of search tactics in video retrieval Transitions from search to display and back occur frequently

17. Implications for research Concept - based coding allows comparisons across IR systems Concept - based coding may yield new insights into people ’ s searching behaviors Behaviors, as recorded in transaction logs, don ’ t tell us what we ’ d like to know about cognition

18. Questions and comments ? Open Video website : open - video. org Funding provided by NSF Grant IIS 0099638

20. Open Video : Advanced Search

21. Codes for search moves CodeDefinition New searchEnter term for a concept; no other terms yet included. AllNo terms entered; all videos in collection are retrieved. Add conceptAdd a concept not yet in query; implicit AND. Delete conceptDelete a concept from the query. Narrow termReplace a term with a narrower term for the same concept. Broaden termReplace a term with a broader term for the same concept. Replace termReplace a term/concept. Narrow operatorReplace an operator with a narrower operator (OR  AND). Broaden operatorReplace an operator with a broader operator (AND  OR). DisplayDisplay results or modify the results display. CorrectCorrect an error (e.g., spelling error) in the query.