On Using Existing Time-Use Study Data for Ubiquitous Computing Applications UbiComp ’08 Kurt...

On Using Existing Time-Use Study Data for Ubiquitous Computing Ap-plications

UbiComp ’08Kurt Partridge and Philippe Golle

Palo Alto Research Center

SangJeong

Time-Use Studies

• American Time-Use Survey (ATUS)▫USA, Bureau of Labor Statistics▫ To estimate work not included in economics measures

(e.g., home childcare)• Many versions▫ Korean 1999▫ Japanese over 200,000▫American Heritage Time Use Study (AHTUS)

ATUS + 4 older studies▫Harmonized European Time Use Study (HETUS)▫Multinational Time Use Study (MTUS)▫www.timeuse.org

Excerpt of Time-Use Data

Activity by Time of Day

ATUS Activity Classification

Suitability of Time-Use Data for Ubi-comp• Duration difference▫ A couple hours vs. an instant to tens of minutes▫ “eating breakfast” vs. “scooping granola, pouring milk, lifting

spoon, …”▫ Cannot predict activities at detail, but can bias predictions to-

ward more likely activities

• Domain specificity difference▫ All activities in an entire day vs. a limited domain (physical mo-

tion, in-home activities of daily living, mechanical repair)▫ Can benefit from cross-domain inferences

• Cognitive interpretation difference▫ Participant and interviewer vs. sensor▫ Can collect data of privacy-sensitive activities, e.g. bathroom

use

Inferring Activity from Context

Using maximum likelihood classifier / tenfold cross-validation

Activity Inference Accuracy, by Location

Further Research Questions

• How much do time-use activity and location tax-onomies vary?

• What issues arise when adopting an activity tax-onomy for a ubicomp application?

• What methodologies used by time-use studies can be adopted in ubicomp systems?

• How can ubicomp contribute to time-use study re-search?