Archive for the ‘ubicomp2008’ Category

2 ubi apps: chat hotsposts and affective diary

Thursday, November 13th, 2008

A couple of cool applications from the Mobile Life Centre in Kista, Sweden

1. Ubiquitous chat hotspots
“Nicolas Belloni of Mobile Life shows an interesting app that uses your phone’s GPS system to create chat hotspots anywhere in the world. When you log in, the system knows where you are and, presumably, you can discuss local topics with friends and relations in that chat room. It’s still in beta, but it’s quite interesting, especially for tourists and international stalkers.” (pdf of Ubicomp workshop)

2. Affective Diary: Your computer knows you’re blue
A little project involving a PC-based application and a body sensor that tests galvanic skin response. When you’re excited, a little blob on the screen turns red and upright and when you’re relaxed the blob is blue and sleepy. The system allows you to watch a timeline of your blobs allowing you to see when and where you were most excited or agitated and even provides biofeedback. One tester found that she was most agitated when her son was leaving to go back to Paris. By noting this, she learned she could tell her son she missed him and feel much better after he left instead of holding it in and getting herself upset. It’s a very humanist – and friendly – approach to technology.

Check also this paper by Lars Erik Holmquist «Automated Journeys – Automated Connections?» (pdf)

Ubicomp 2008

Monday, September 29th, 2008

Many blogs have been covering Ubicomp and, a couple of days ago, I promised to write down my own coverage. Here you go ;-)

The first day I attended the Automated Journeys workshop organized by Arianna Bassoli (who gave a talk at UCL a while back), Johanna Brewer (whose recent work has been covered here; for more, check her blog), and . The workshop’s format was not  traditional. As part of the workshop, we went out and had lunch :-), and, while doing so, we observed how people in Seoul use technologies.  Then, we came back and, through group discussions and hands-on design brainstorming sessions, we produced  4 envisagements that  critically reflected on technological futures. It was very engaging! I hope other workshops will replicate/mutate this format. I wished I could attend at least two of the  other workshops on offer: Ubiquitous Systems Evaluation partly organized by Chris Kray (I am in debt with him, and he knows why ;-)) and Devices that Alter Perception partly organized by Carson Reynolds.

At Ubicomp, the speakers did not suffer from powerpoint karaoke syndrome, and their slides were generally  well-designed – less text, more images. That is largely because the ubicomp’s community is made of design-conscious (CHI) researchers. Few talks are already available on slideshare.

Here are few papers I personally found intriguing because of their algorithms, their evaluation, or their interesting ideas. At the end of this post, I’ll point to few datasets that have been used and can be of interest ;-)

1. Algorithms

Navigate Like a Cabbie: Probabilistic Reasoning from Observed Context-Aware Behavior. Brian D. Ziebart showed a new way of making route predictions. He used a probabilistic model  presented at AAAI “Maximum Entropy Inverse Reinforcement Learning“.  Interestingly, he showed that the model works upon data that is noisy and imperfect.

Pedestrian Localisation for Indoor Environments. Oliver Woodman proposed a way of  tracking people indoor. Oliver and Robert showed how to combine a foot-mounted unit, a building model, and a particle filter to track people in a building. They experimentally showed that users can be effectively tracked within 1m without knowing their initial positions. Great results! It’s a paper well worth reading!

Discovery of Activity Patterns using Topic Models. Bernt Schiele presented a new method for recognizing a person’s activities from wearable sensors.  This method adapts probabilistic topic models and has been shown to recognize daily routines without user annotation.  One of Bernt’s students had an interesting poster on detecting location transitition using sensor data (pdf).

2. Evaluation

A couple of papers (including the great work done by Matthew Lee)  used a method called the Wizard of Oz evaluation. The general idea is to simulate those parts of the system (e.g., speech recognition) that require most effort in terms of development or to assess the suitability of your interface(see “Wizard of Oz studies – why and how” (pdf) for more).

Flowers or a Robot Army? Encouraging Awareness & Activity with Personal, Mobile Displays by Sunny Consolvo et al.  They designed a system that makes it possible for mobile users to self-monitor their physical activities and conducted a greatly designed 3-month field experiment.

Reflecting on the Invisible: Understanding End-User Perceptions of Ubiquitous Computing (pdf). Erika Shehan Poole detailed end-user perceptions of RFID technology using an interesting qualitative method that combines structured interviews and photo elicitation excercises. Erika and her mates show that, by using this method, one is able to uncover perceptions that are often difficult for study participants to verbalize.  One of her findings: many people believed that RFID can be used to remotely tract the location of tagged objects, people, or animals!

3. Interesting Ideas

Bookisheet: Bendable Device for Browsing Content Using the Metaphor of Leafing Through the Pages. Trash your mouse. Jun-ichiro Watanabe presented a VERY promising interface (a book made of two thin plastic sheets and bend sensors) with which  a user can easily scroll digital content such as photos. The user  does so by simply bending one side of the sheet or the other.

Towards the Automated Social Analysis of Situated Speech Data. To automatically understand individual and group behavior, Danny Wyatt et al. recorded the coversational dynamics of 24 people over 6 months. They did so using privacy-sensitive techniques. By using this type of studies, researchers may well  gain broad sociological insights.

The Potential for Location-Aware Power ManagementRobert Harle showed how to dinamically optimize the energy consumption of an office. Very interesting problem-driven research!


Accessible Contextual Information for Urban Orientation
. Jason Stewart  presented a prototype of a location-based  service with which mobile users share content (see their project’s website)

Enhanced Shopping: A Dynamic Map in a Retail Store.  Alexander Meschtscherjakov  presented a prototype for mobile phones that displays  customer activities (e.g., customer flow) inside a shopping mall

Spyn: Augmenting Knitting to Support Storytelling and Reflection (pdf). Daniela K. Rosner‘s presentation was masterfully designed! She walked us through her expirience of designing Spyn – a system for knitters to record, playback, and share information involved in the creation of their hand-knit artifacts. She showed how her system enriches the knitter’s craft

Picture This! Film assembly using toy gestures. Cati Vaucelle (who keeps a cool blog) presented a new input device embedded in children’s toys for video composition.  As they play with the toys to act out a story, children conduct film assembly.

4. Datasets

Understanding Mobility Based on GPS Data by et al. used GPS logs of 65 people over 10 months (the largest dataset in the community!) to evaluate a new way of  inferring people’s motion modes from their GPS logs

Accurate Activity Recognition in a Home Setting (pdf) by Tim van Kasteren et al. used 28 days of sensor data about one person @ home and corresponding annotations of his activities (e.g., toileting, showering, etc.) to evaluate a new method for recognizing activities from sensor data.

Discovery of Activity Patterns using Topic Models by Tam Huynh et al. used 16 days of sensor data from a man who was carrying  2 wearable sensors to test their method for automatically recognizing activities (e.g., dinner, commuting, lunch, office work) from sensor data.

On Using Existing Time-Use Study Data for Ubiquitous Compting Applications by Kurt Partridge and Philippe Golle how to use data (e.g. people’s activities and locations) that has been collected by governments and commercial institutions to evaluate ubicomp systems.

The Potential for Location-Aware Power Management by Rober Harletested on location data of 40 people in 50-room office building for 60 working days his proposed strategies for dinamically optimizing the energy consumption of an office.

(ubicomp2008)

“Making Mobile Raters Stick to their Word ” @ Ubicomp

Monday, September 22nd, 2008

In few hours I will present MobiRate. Fortunately, the slides are ready ! See them next. A short description follows.

P.S. I’ll blog about Ubicomp shortly. For now, look at the great coverage by Albrecht Schmidt  ;-)

MobiRate

View SlideShare presentation or Upload your own. (tags: trust systems)

Q&A Session (at the conference):

Q> You have shown that MobiRate effectively protects against *indepedent* malicious individuals. What if  malicious individuals collude?
A> Colluding malicious peole will not be able to tweak  ratings because they cannot produce fake crypto material. However, if malicious people collude, one may well run into updating problems. Phones update their ratings  while they move and, consequently, there are   time windows in which ratings are not up-to-date. During those time-windows, colluding people may succeed in attacking the communities they are in  (e.g., in flooding the system with spam content).

Q>  Phones that run MobiRate audit each other. Are their users aware of that?
A> We have assumed that, in downloading and running MobiRate, people silently agree with  the possibility of their phones being “auditors”. However, people should be able to step back and refuse to be auditors at times; for example, whenever they are running out of battery. This feature should be definetely
included in the next version of MobiRate.

Q> Your solution is general, in that, it is able to collect and store not only user ratings but also user activities!
True.  Instead of monitoring ratings, one could force people in keeping a record of their activities. Before deploying MobiRate, we should carefully think about its misuses and try to prevent them. A good starting point could be to understand how “historical misuses of technology can be studied to be avoided in the future” (link)

Short Description of MobiRate:

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