These slides are made by Rianne Nieland and were presented by her to finalize her Master project Information Sciences

1. Talking to Linked Data:
Comparing voice interfaces for
general-purpose data
Rianne Nieland
Supervisor: Victor de Boer
Vrije Universiteit Amsterdam

2. Context & Problem Statement
• Web = big information space
o Contains useful information for people in developing countries
• Like governmental and medical information, and information about
plants and trees on Wikipedia
• People in developing countries:
o No internet access
o Often low literate
o Do have mobile phones
• Solution: Voice-based access to Web data using
GSM network
• Research: Develop voice
interfaces for general-purpose
datasets

3. Wikipedia vs DBpedia
• Natural language text
• And structured
information, like infobox,
images and links to other
pages
• Extracts structured
information of Wikipedia
• DBpedia ontology:
classes and properties
• Data interlinked with
other data sources
• Very lightweight way to
share, re-use and
integrate datasets

4. Research Questions
How can information from Wikipedia efficiently
be made available using voice interfaces for GSM?
1. What are the requirements of a good voice
interface for Wikipedia and DBpedia concepts?
2. What are good methods for converting Wikipedia
and DBpedia concepts to voice interfaces?
3. How do users perform on the Wikipedia and
DBpedia voice interface in terms of speed, error
rate and usability?

5. Approach
Experiment
Developing conversion algorithms (Process)
Developing voice user interface (Output)
Requirements elicitation
Literature study

6. Requirements elicitation
• Input requirements
o Dual-Tone Multi-Frequency input
o Local phone line
• Process requirements
o Overview of page
o Eliminate repetitions
o Feedback
o Error recovery
• Output requirements
o System’s voice: female + text to speech
o Nonverbal sounds

7. Voice user interface
• Basic call flow structure:
1. Welcome message + page menu
2. Section menu
3. Subsection menu
4. Reads chosen (sub)section to user
• Voice interfaces have same basic call flow structure
• But different input sources

8. Process of voice interfaces
Input:
Wikipedia
/DBpedia
? Output:
Call flow

9. Process of voice interfaces
Input:
Wikipedia
/DBpedia
Proces:
Conversion
Output:
Call flow

10. Conversion steps
• DOMXPATH queries
• Section menu:
o Elements with class mw-
headline, except h3 and h4
• Subsection menu:
o h3 elements
• Read (sub)section
o p en li elements
• SPARQL queries
• Section menu:
o Abstract
o Nutritional values
o Biological classification
o Associated food, persons and
organizations
• Subsection menu &
Read (sub)section
o SPARQL queries

11. Experiment
• 16 participants
• Domain crops
• Each participant tests both voice interfaces by
answering questions with the voice interfaces
• 2 question sets of each 3 questions
• Divided participants into 4 groups:
o First Wikipedia (W) with question set 1 and then DBpedia (D) with question
set 2 (W1D2)
o W2D1
o D1W2
o D2W1

12. Experiment
1. Verbal explanation
2. General questionnaire (gender, age, purposes of
mobile phone usage and usage of voice
interfaces)
3. Test first voice interface by answering questions
4. Fill in IBM’s usability satisfaction questionnaire
5. Test second voice interface by answering questions
6. Fill in IBM’s usability satisfaction questionnaire

13. Results: Speed
• Wikipedia voice interface average time 2:53
minutes
• DBpedia voice interface average time 2:22 minutes
• No significant difference  Both voice interfaces
equally fast
• Also no learning curve found

14. Results: Error rate
• In general both voice interface have significantly
the same error rate
• For question 2 of question set 1 Wikipedia has a
significantly lower error rate

15. Results: Usability
• Usability is divided into 4 scores:
o Overall satisfaction
o System usefulness
o Information quality
o Interface quality
• In general no significant difference between
Wikipedia and DBpedia voice interface for all
scores
• When voice interfaces are tested first:
o Wikipedia scores higher on overall satisfaction and information quality

16. Discussion
• WiFi connection sometimes did not work
• DBpedia was offline a number of times
o DBpedia backup voice interface
• Participants are used to access textual version of
Web
• DBpedia contains very little information
• DBpedia voice interface is domain specific

17. Conclusion
• To make information from Wikipedia efficiently
available using voice interfaces for GSM:
o Requirements should be met
o Conversion methods used in this research should be considered, because
they work efficiently
o Both normal Web data, Wikipedia, or Linked Data, Dbpedia, can be used

18. Future work
• Can be used in developing countries
o Should use local languages
o Local phone number
o Should be tested there outside a lab
o Investigate what information these people need
• Broaden scope to whole Wikipedia and DBpedia