1. Mobile Photos April 17, 2008

2. Auto Extraction of Flickr Tags Unstructured text labels Extract structured knowledge Place and event semantics Scale-structure identification Spatial and temporal patterns at various scales Events/place as small bursts in time/space Standard IR metrics to evaluate performance ◦low precision: most of the items retrieved are irrelevant ◦low recall: may fail to retrieve some documents that are actually relevant to the search question Ground truth manual annotation, 803 tags

3. World Explorer aggregate knowledge from unstructured tags “representativeness” of a tag primary and secondary tags for visualizing markers (text size) on a map tourism tasks

4. Photos on the Go social, spatial (specific places), topical on mobile phone Zurfer: wallet for world’s media self-selected >500, 69 active, 9 interviewees grounded with mobile logs nearby, latest from contacts, own photos, highly ranked Flickr ease of use; multitasking; social interaction and physical convenience 3 use modes: Task Time, Down Time, and Killing Time. Implications: speed, location content, social content, 3 use modes

5. Mobile Advertising (B-MAD) location-aware mobile advertisements permission-based needs ads complemented with personalization push service quantitative: device discovery and latency of network (positioning and ad delivery) qualitative: user reaction to ads figure 6 scale: which one’s neutral? privacy and security issues