QianYing Wang

Context data in geo-referenced digital photo collections

Given time and location information about digital photographs we can automatically generate an abundance of related contextual metadata, using off-the-shelf and Web-based data sources. Among these are the local daylight status and weather conditions at the time and place a photo was taken. This metadata has the potential of serving as memory cues and filters when browsing photo collections, especially as these collections grow into the tens of thousands and span dozens of years. We describe the contextual metadata that we automatically assemble for a photograph, given time and location, as well as a browser interface that utilizes that metadata. We then present the results of a user study and a survey that together expose which categories of contextual metadata are most useful for recalling and finding photographs. We identify among still unavailable metadata categories those that are most promising to develop next.

The connector service-predicting availability in mobile contexts

In this thriving world of mobile communications, the difficulty of communication is no longer contacting someone (the receiver), but rather contacting them in a socially appropriate manner. Ideally, senders should have some understanding of a receivers availability in order to make contact at the right time, in the right contexts, and with the optimal communication medium. This paper describes our ongoing research on the Connector, an adaptive and context-aware service designed to facilitate efficient and appropriate communication. We describe a set of empirical studies whose results converge upon the important subject of peoples availability in mobile contexts.s

Natural language query vs. keyword search: effects of task complexity on search performance, participant perceptions, and preferences

A 2x2 mixed design experiment (N=52) was conducted to examine the effects of search interface and task complexity on participants’ information-seeking performance and affective experience. Keyword vs. natural language search was the within-participants factor; simple vs. complex tasks was the between-participants factor. There were cross-over interactions such that complex-task participants were more successful and thought the tasks were less difficult and reported more enjoyment and confidence when they used keyword search vs. natural language queries, while the opposite was found for simple-task participants. The findings suggest that natural language search is not the panacea for all information retrieval tasks: task complexity is a critical mediator. Implications for interface design and directions for future research are discussed.

Can you talk or only touch-talk: A VoIP-based phone feature for quick, quiet, and private communication

Advances in mobile communication technologies have allowed people in more places to reach each other more conveniently than ever before. However, many mobile phone communications occur in inappropriate contexts, disturbing others in close proximity, invading personal and corporate privacy, and more broadly breaking social norms. This paper presents a telephony system that allows users to answer calls quietly and privately without speaking. The paper discusses the iterative process of design, implementation and system evaluation. The resulting system is a VoIP-based telephony system that can be immediately deployed from any phone capable of sending DTMF signals. Observations and results from inserting and evaluating this technology in real-world business contexts through two design cycles of the Touch-Talk feature are reported.

Visual interface and control modality: an experiment about fast photo browsing on mobile devices

We examined the strengths and weaknesses of three diverse scroll control modalities for photo browsing on personal digital assistants (PDAs). This exploration covered nine alternatives in a design space that consisted of three visual interfaces and three control modalities. The three interfaces were a traditional thumbnail layout, a layout that placed a single picture on the screen at a time, and a hybrid that placed one large photo in the center of the display, while also displaying a row of neighboring thumbnails at the top and bottom of the screen. In a user experiment we paired each of these interfaces with each of the following three scroll control modalities: a jog dial, a squeeze sensor, and an on-screen control that was activated by tapping with a stylus. We offer a simple model that classifies our experiment’s interfaces by how much they provide visual context within the photo collection. The model also classifies the scroll modalities by how tightly they correlate scroll input actions to effects on the screen. Performance and attitudinal results from the user experiment are presented and discussed.

A cost-effective three-in-one personal digital assistant input control

Abstract We attach an inexpensive pressure sensor to the side of a personal digital assistant and use it as three input devices at once. Users can squeeze the device to provide near-continuous input to applications. At the same time the drivers interpret a sudden full squeeze as the push of a virtual button. A users sudden pressure release while squeezing is detected as the push of a second virtual button. We briefly describe our hardware and signal processing techniques. The remainder of the writing describes an experiment that explores whether users can cope cognitively with the 3-in-1 control. We compare against a three-control setup consisting of a jog wheel and two physical buttons. We show that the three-in-one control enables a 13% faster reaction time over the three-control one, but that the three-in-one control suffers a 4% penalty in the accuracy of users choosing between the two buttons in response to cues from an application. We show that a good choice of application cue is more important for assuring accuracy in the 3-in-1 than in the more traditional set of separate controls.