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lecture 18: tagging and folksonomy
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metadata
is:“structured information that describes, explains, locates, or otherwise makes it easier to retrieve, use, or manage an information resource”
(NISO)
it allows systems to collocate related information, and helps users find relevant information
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metadataways of creation
generally in two ways:
professional creation (professionals working with complex, detailed rule sets and vocabularies)
author creation (authors of documents provide metadata along with their creations)
are ontologies the result of that???
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metadatathird (new) way
user- created metadata
users of the documents and media create metadata for their own individual use that is also shared throughout a community
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folksonomywhat is it?
it is a people's taxonomy
is composed of terms in a flat namespacethere is no hierarchy, no parent- child or sibling relationships between these terms
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folksonomywhat is it?
the set of terms (called tags) that a group of users tagged content with, they are not a predetermined set of classification terms or labels
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folksonomy…
the cumulative force of all the individual tags can produce a bottom-up, self-organized system for classifying items on the web
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what is tagging?introduction
a tag is a non-hierarchical keyword or term assigned to a piece of information - such as an internet bookmark, digital image, or computer file
(Wikipedia)
tagging – to mark with a tag; to label, identify, or recognize with or as if with a tag- a unique and powerful way of organizing information
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what is tagging?tagging system
three “components”-users-resources-tags
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tagging systemusers
the people who employ a tagging system (sometimes also called taggers) – they create the tags, and sometimes they add resources
have a variety of different interests, needs, goals, and motivations – but they are trying to achieve some larger goal – such as sharing a photo or labeling a document so they can find it later
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tagging systemresources
are items that users tag
a resource can be just about anything – a book, a Web page, a video, or even a location
within each tagging system, resources often share some common properties – they are books, or photos, or …
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tagging systemtags
the keywords added by users are tags
can be just about any kind of term, they can be descriptions of the resource’s subject matter, its location, its intended user, a reminder, or something else entirely – can be individual words or phrases
tags are essentially metadata about the resource
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tagging systemtags
tags are more than just metadata in an application – they are a tool people use to track, share, and find information
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tagging systemtag cloud
is a method of presenting tags where the more frequently used tags are emphesized
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tagging systemtag cloud – example
www.wordle.net
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tagging system…
all tagging happens in the context of a system, and the system defines what kind of tagging can take place
for example, the system may allow users to add their own resources or not, may allow to tag any resource or not, may forbid certain kinds of tags
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tagging systemperspectives …
tagging sitsat the intersection of three establishedfields
Social Software
Personal Information Management
InformationArchitecture
tagging
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tagging systeminformation architecture
the structural design of shared information environments andthe art and science of organizing and labeling web sites, intranet, online communities, and software to support usability and findability
information architects focus on using controlled vocabularies, search-and-browse systems
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tagging systemsocial software
applications that people use to communicate, collaborate, and share online
people who design social software are interested in facilitating group interaction within the system
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tagging systempersonal information management
“refers to the practice and study of the activities people perform in order to acquire, organize, maintain, retrieve, and use information items such as documents, web pages, e-mail messages …”
(Wikipedia)
they are programs for managing information and methods for keeping yourself on track – help you file, track, and find your information when you need it
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tagging systemtensions …
personal <-> social
do people tag primary for their own benefit?or are they motivated to share information with a group …?
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tagging systemtensions …
idiosyncratic<-> standard
should tags be unique?or should be standardized so they can be used for browsing and searching?
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tagging systemtensions …
freedom<-> control
does the system give users complete freedom?or does it influence or control their tags?
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tagging systemtensions …
amateur<-> expert
how qualified are the people who do tagging?should tags contributed by amateurs count as much as tags created by experts?
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tagging why matters
it is popularit is multifaceted it is flexibleit is also made for the stream – the constant flow of information we experience online
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tagging motivation
ease of use-tags are simple
just typing few words-tags are flexible
tags can be whatever you need them to be
-tags are extensibleyou can always add new tags
-tags can be aggregated
… can be messy and may not conform to any recognizable pattern
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tagging motivation
managing personal information- do not need to consider the whole
categorization scheme, you just add tags- you can add any tags, instead of finding the
one category that is the best fit- re-categorization is easy if we make a mistake
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tagging motivation
collaborating and sharing- you can explore topics using the tags of other
users- other users may be experts- you may use tags to connect with other users
who share interests
having fun
expressing yourself
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tagging system architecture
requires to set up rules about your users (who they are and how they join the system), your resources (how they are added to the system), and tags (who can tag which resources)
how users interact with each other
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tags as metadatakinds of metadata
metadata:-helps you (or others) find data you want-helps you manage your data-lets you relate your data to other data you own, as well as other data out there in the world
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tags as metadatakinds of metadata
descriptive – provide details about the resourceadministrative – used to manage a collection of resources (for example, date a resource was acquired, the person who owns the rights to the resource)structural – used to associate the resource with other resources (for example, volume of books, maps of how individual files relate to each other)
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tags as metadatakinds of metadata
tag type exampledescriptive webdesign, drama, sushi
gardening, musicresource blog, book, video, photoownership/source nytimes, genesmith (author)opinion cool, funny, lameself-reference mystuff, minetask organizing todo, workplay/performance helo3, poetry
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tags …taxonomies and controlled vocabularies
two kinds of classification systems – define relationships between terms
help us understand and navigate concepts by making language less ambiguous, by connecting concepts, and by capturing the relationships between objects observed in the real world
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tags …controlled vocabularies
a system for managing the meaning of words – it removes ambiguity of language
synonym rings – give two or more words an equivalent meaningauthority files – as above but one of the words is identified as a preferred term
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tags …taxonomies
establishes parent-child relationships between terms, are typically hierarchical
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tags …enriching taxonomy with tags
bubble-up approachtags are attached to a resource, for example, a songthose tags are “bubble-up” from several songs to describe their parent item, albumalbum tags are then bubbled up again to describe the artist
relationships between resources are preserved while capturing the descriptive terms of users
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folksonomyintroduction
it is a term used to describe the bottom-up classification systems that emerge from social tagging
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folksonomyintroduction
the relationships between tags are inferred based on their usage patterns
no formal relationships parent-child like in taxonomyno equivalences between terms as in a controlled vocabulary
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folksonomyintroduction
ajax
webdesign
css HIV
cxcr4
ccr5
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folksonomy- independence
users are free to choose their tags
some systems offer suggestions – a tool aimed to help users add tags more easily and efficiently
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folksonomy- aggregation
pulling all the tags together in an automated way – this creates folksonomy
manual sampling of tags, few users – not a folksonomy
– based on users’ activities and interests
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folksonomy- inference
relationships between tags are inferred from their use
they are based on the language and usage patterns of real users
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folksonomy- methods to infer semantic relationships
-counting tags to see which is most popular-co-occurrence counts which tags are used together (loose approximation of the associative relationships)-clustering of tags that have a high probability of co-occurence
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folksonomywhen to use
-nomenclature is uncertain or evolving-dynamic information space-semantic relationships are not critical-multiple viewpoints are desirable-you can tap in an active base of users
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from folksonomy to ontologysuper-class relationships
tags that co-occur with other tags often are thought to be more general than more specific-tags that co-occur with other tags less often
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from folksonomy to ontologysuper-class relationships
for example"music" co-occurs with both "piano" and "guitar", and as such can be suspected being a super-class of bothon the other hand, "piano" probably does not co-occur with more possible tags than "music" and usually co-occurs with "music" and so it likely is a subclass
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from folksonomy to ontologysynonym relationships
detecting synonyms is actually counter-intuitive, since I believe that the same user will not tag a URI both "computer" and "PC," but will probably only pick one of those
however, groups of users will use different synonyms, and over time most of the convergence will come from synonyms being merged.
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from folksonomy to ontologystructured relationships
tags that co-occur often might have a facet, or structured relationshipthese may be pairs or trids
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from folksonomy to ontologystructured relationships
for example"book" and "author" and "Mark Twain" is a triadic ("triple" on the Semantic Web) relationship, and if these co-occur quite often they are probably a relationshipin fact, one would suspect that most co-occurences are pairs, like "author" and "Zadie Smith," or "book" and "Mark Twain," and making these work with the Semantic Web would be slightly more difficult
