The Semantic History Extension for SMW

Jie Bao and Li Ding Rensselaer Polytechnic Institute

2009 Aug 6th

Motivation

The MediaWiki “recent changes” page and “history” tab

• Allows only very limited search of edits• Does not capture the “semantics” of revision

summary – e.g., “typo fix”, “add a source from CNN”

• Does not provide triple-level changes• Can’t track temporal knowledge easily, e.g., Alice

was Undergraduate in the spring but Ph.D. student in the summer.

The Design

A demo system http://tw.rpi.edu/semhis

User makes edits

The Semantic History (SH) extension

captures edit actions

SH Generates “hidden pages” for revisions and triple changes.

SMW generates semantic annotations based on templates

Applications use semantic annotations

• Query• Statistics• Visualization• Explaination• …

(can be customized)

Revision Capture

A typical revision page

{{SH_Rev|3353|20090714211611|User:Baojie|Jin Guang Zheng}}

{{SH_UseTemplate|Template:Member of|2931}}

{{SH_Categories|PhD Student}}

Those pages are hidden from common users

Triple Diff• A typical triple page

{{SH_Triple|RPI|DefinedBy|Jie Bao}} {{SH_Add|1454|20090708190303|

User:Baojie}}{{SH_Add|M20090708235158|

20090708235158|User:Baojie}}{{SH_Delete|3305|

20090713115342|User:Baojie}}{{SH_Obsolete|1}}

Semantic Summary

A revision page with semantic summary

{{SH_Rev|2462|20090712064807|User:Baojie|Main Page}}

{{SH_Summary|reason::to demo semantic summary; source::none; category:Test Edit; something not useful}}

{{SH_Minor}}

How to explain summary is up to the wiki admin (by designing “Template:SH_Summary”)

Usage Examples

Provenance tracking

Who has changed the first name of James Hendler? http://tw.rpi.edu/proj/semhis.wiki/index.php/Example_4

Query

Semantic Recent Changehttp://tw.rpi.edu/proj/semhis.wiki/index.php/Semantic_recent_changes

Statistics

Which domain has attracted more changes: University or Person?http://tw.rpi.edu/proj/semhis.wiki/index.php/Example_5

Visualization

Edit trend from 2009-07-07 to 2009-07-13http://tw.rpi.edu/proj/semhis.wiki/index.php/Example_10

Temporal Reasoning

Which papers of Jie Bao are "Tetherelss World Publication"?http://tw.rpi.edu/proj/semhis.wiki/index.php/Example_8

Explanation• Step 1: the triple "Jie Bao Member_of ITA" is created at revision

rev:2934, which does not directly generate this triple.• Step 2: rev:2934 uses template "Template:Member of" of revision 2931.• Step 3: rev:2931 may generate properties: member,member of• Thus, one possible explanation of "Jie Bao Member_of ITA" is the

combination of rev:2934 to Jie Bao and rev:2931 to Template:Member of.

The process is encoded by “Template:Explain”

Why Jie Bao is a member of the project ITA?http://tw.rpi.edu/proj/semhis.wiki/index.php/Example_11

Conclusions• “Semantic History” allows revision information in SMW to be

represented in a semantic way.• Use SMW as database – semantic support built in and

seamless integration with other SMW tools. • Customization by template, e.g., for vocabulary and semantic

summary syntax• Allows many more applications than we demonstrated: trust

computation, advanced explanation, revision as linked data, etc.

• Will be released at http://www.mediawiki.org/wiki/Extension:SemanticHistory