Models of Context Why? –So we talk about it, write about it, argue about it –So we can show it...

Models of Context

• Why?– So we talk about it, write about it, argue about

it– So we can show it to the user– So the user can understand it…– …and change it

Our model

• Context as a dynamic process with historic dependencies

• Context is comprised of a series of context states, like scenes in a movie

• We have developed:– An interactional model of context– A software implementation of that model– Web service interface for the software– Integrated prototype using sensor inputs

Context awareness for MOBIlearn

Context Awareness• Purpose:– Context enables appropriate action - in this

case learning

• Process:Context = a dynamic and historical process…

…constructed from context states…

… which are constructed through interaction between actors, situations, objects and activities... etc

Context Model

ContextWhat’s going on over time

Context SubstateElements from the Learner and Setting that are

relevant to the current focus of learning and desired level of context awareness

Context StateElements from the Learning and Setting at one particular point in time, space, or goal sequence

Mapping this on to metadata

Content Setting

Metadata

Learner +

= Learning Objects+ Resources+ Services

= Context SubstateContext

awareness

Basic Operation

1. Context features acquired or input2. Context substate constructed from context

features3. Unsuitable content excluded4. Remaining content ranked using current

context state5. Rankings output to delivery subsystems

Architecture

ContextAwarenessSubsystem

ContentServer

Sensors

User inputUser profile

Contentmetadata

Contentrecommendations

XML

XML

XML

XML

XML

Content

Environment

Objectives

• Use a model of context to dynamically select content

• Implement tracking system to provide real-time user location to the context system

• Evaluate technical issues surrounding implementation

• Perform trials of the system in mock-up gallery

Current status at UoB

• Context Awareness Subsystem– Java implementation– Available as a web service– Reads metadata from available content– Provides recommendations

• User tracking– Ultrasound positioning system– Tracking device attached to learner’s iPaq

• Content delivery– Pushed delivery of simple XHTML content to viewer on

iPaq

• Two factors:– Where is the user?

– How long have they been there?

• Content recommended based on painting (from position) and inferred level of interest (from time)– 10s = low = short title

– 20s = medium = short description

– 30s = high = full text

Context awareness

• Trials to be run at Nottingham Castle Museum in September• Testing underway in mock-up art gallery• Technology:

– Ultrasound positioning sensors– Wireless PDAs– Content & metadata server– Other MOBIlearn system services

• Collaborative services• Multimedia streaming

• Soon to be installed:– RFID tags & readers for iPaqs

Test set-up

Title• .

User Trials

• Small scale user trials, December 2003• Using limited contextual data...

– Location– Location of others– Current question– Questions answered by others– Time on question

• ...to modify content:– Painting/artist details– Recommended next question

Title

• .

• It works:– Learners able to quickly find relevant information and successfully

answer the questions

• Open issues:– Interface: crucial to get the representation right– Understanding: some people weren’t quite sure why the system

did what it did, and were surprised by the constantly changing list of options

– Distraction vs Engagement: offering multiple choices led to sidetracking or encouraged people to further their exploration of the content

– Mixed content: need to to distinguish questions, content, physical resources

Issues from user trials

Navigation metaphor

• Context aware navigation of content is replacing the more familiar web browser metaphor

• User interface issues include:– Should we provide web-style navigation (eg Back,

Forward, History)

– Will users exploit the context metaphor for content navigation (eg movement = navigation) or will it hinder them?

Next 3-6 months

• User trials– Uffizi– Nottingham Castle Museum

• Development– Display of context model to user– Provision of user controls, eg ‘hold’ button and ‘Why was

this recommended to me?’– Exploration of ‘context navigation metaphor’– Use of context history to influence current

recommendations