Where to next for social metadata? User Labor Markup Language?

The noughties will go down in history as a great decade for metadata, largely as a result of XML and RDF. Here are some highlights so far, off the top of my head: MARCXML, MODS, METS, MPEG-21 DIDL, IEEE LOM, FRBR, PREMIS. Even Dublin Core – an initiative born in the mid-1990s – has taken off in the noughties owing to its extensibility, variety of serialisations, growing number of application profiles and implementation contexts. Add to this other structured data, such as Semantic Web specifications (some of which are optimised for expressing indexing languages) like SKOS, OWL, FOAF, other RDF applications, and microformats. These are probably just a perplexing bunch of acronyms and jargon for most folk; but that's no reason to stop additions to the metadata acronym hall of fame quite yet...!

Spurred by social networking, so-called 'social metadata' has been emerging as key area of metadata development in recent years. For some, developments such as collaborative tagging are considered social metadata. To my mind – and those of others – social metadata is something altogether more structured, enabling interoperability, reuse and intelligence. Semantic Web specifications such as FOAF provide an excellent example of social metadata; a means of describing and graphing social networks, inferring and describing relationships between like-minded people, establishing trust networks, facilitating DataPortability, and so forth. However, social metadata is increasingly becoming concerned with modelling users' online social interactions in a number of ways (e.g. APML).

A recently launched specification which grabbed my attention is the User Labor Markup Language (ULML). ULML is described as an "open protocol for sharing the value of user's labor across the web" and embodies the notion that making such labour metric data more readily accessible and transparent is necessary to underpin the fragile business models of social networking services and applications. According to the ULML specification:

"User labor is the work that people put in to create, improve, and maintain their existence in social web. In more detail, user labor is the sum of all activities such as:

• generating assets (e.g. user profiles, images, videos, blog posts),

• creating metadata (e.g. tagging, voting, commenting etc.),

• attracting traffic (e.g. incoming views, comments, favourites),

• socializing with other people (e.g. number of friends, social influence)

in a social web service".

In essence then, ULML simply provides a means of modelling and sharing users' online social activities. ULML is structured much like RSS, with three major document elements (action, reaction and network). Check out the simple Flickr example below (referenced from the spec.). An XML editor screen dump is also included for good measure:

<?xml version="1.0" encoding="UTF-8"?>
<ulml version="0.1">
<channel>
<title>Flickr / arikan</title>
<link>http://fickr.com/photos/arikan</link>
<description>arikan's photos on Flickr.</description>
<pubDate>Thu, 06 Feb 2008 20:55:01 GMT</pubDate>
<user>arikan</user>
<memberSince>Thu, 01 Jun 2005 20:00:01 GMT</memberSince>
<record>
<actions>
<item name="photo" type="upload">852</item>
<item name="group" type="create">4</item>
<item name="photo" type="tag">1256</item>
<item name="photo" type="comment">200</item>
<item name="photo" type="favorite">32</item>
<item name="photo" type="flag">3</item>
<item name="group" type="join">12</item>
</actions>
<reactions>
<item name="photo" type="view">26984</item>
<item name="photo" type="comment">96</item>
<item name="photo" type="favorite">25</item>
</reactions>
<network>
<item name="connection">125</item>
<item name="density">0.167</item>
<item name="betweenness">0.102</item>
<item name="closeness">0.600</item>
</network>
<pubDate>Thu, 06 Feb 2008 20:55:01 GMT</pubDate>
</record>
</channel>
</ulml>

The tag properties within the action and reaction elements are all pretty self-explanatory. Within the network element "connection" denotes the number of friend connections, "density" denotes the number of connections divided by the total number of all possible connections, "closeness" denotes the average distance of that user to all their friends, and "betweenness" the "probability that the [user] lies on the shortest path between any two other persons".

Although the specification is couched in a lot of labour theory jargon, ULML is quite a funky idea and is a relatively simple thing to implement at an application level. With the relevant privacy safeguards in place, service providers could make ULML files publicly available, thus better enabling them and other providers to understand users' behaviour via a series of common metrics. This, in turn, could facilitate improved systems design and personalisation since previous user expectations could be interpreted through ULML analysis. Authors of the specification also suggest that a ULML document constitutes an online curriculum vitae of users' social web experience. It provides a synopsis of user activity and work experience. It is, in essence, evidence of how they perform within social web contexts. Say the authors:

"...a ULML document is a tool for users to communicate with the web services upfront and to negotiate on how they will be rewarded in return for their labour within the service".

This latter concept is significant since – as we have discussed before – such Web 2.0 services rely on social activity (i.e. labour) to make their services useful in the first place; but such activity is ultimately necessary to make them economically viable.

Clearly, if implemented, ULML would be automatically generated metadata. It therefore doesn't really relate to the positive metadata developments documented here before, or the dark art itself; however, it is a further recognition that with structured data there lies deductive and inferential power.