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Below is a Wordle of a paper that I’m presenting at NA-CAP@IU 2009 next month:

The paper talks about semantic network representations as emergent cultural entities that are ontologically connected to larger cultural landscapes. I explore semantic networks from a Heideggerian existentialist and phenomenological perspective. I invoke cultural schema theory to bridge the syntactic and lexical elements to the semantic and conceptual dimensions of semantic network graphs and offers reasons why the viability of such graphs as they are currently constructed are insufficient for creating semantic interoperability for our information technologies.

Tags:conference paper, cultural schemas, culture, Heidegger, interoperability, semantics semantic networks
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Well, I set a date for defense of my dissertation proposal. It’ll be on June 12, 2008 at 9:00AM. I’ve got a few more weeks to refine and finish up the proposal. I want to get it to my committee members about four weeks prior.

So what’s my dissertation going to be about? The tentative title is The Ontology of Tags. It’s basically an exploration of the use of tags as representations of cultural schemas, which are the flexible and adaptable cognitive structures that comprise the conceptualizations of an ontology. I adopt a Heideggerian existentialist perspective on ontology, which is phenomenological rather than categorical.

The formal ontologies constructed for information systems today are based on a classical notion of ontology that consists of complex taxonomies comprised of categories and relationships between them. However, formal ontologies are problematic in that they simultaneously crystallize and decontextualize information, which in order to be meaningful must be adaptive in context. In trying to construct a correct taxonomical system, formal ontologies are focused on syntactic precision rather than meaningful exchange of information. It is not fair to claim that syntax is irrelevant, but the meaning we make of information is dependent upon more than its syntactic structure. The semantic content of information is dependent upon the context in which it exists. For true semantic interoperability to occur among diverse information systems, within or across domains, information must be contextualized.

The way to introduce this contextualization is through the notion of culture. Culture is a phenomenon that emerges through the interplay of intrapersonal cognitive structures (i.e., schemas) and the extrapersonal structures of the world. Culture shapes the way we conceptualize the entities and phenomena of the world of our experience. What I describe as culture, Heidegger describes as background, in which we are continually immersed as Dasein. We are always being-in-the-world. Moreover, we are always being-in-becoming, emerging into the world as it were.

My thesis is that ontologies are more properly conceptualized as cultural schemas (i.e., shared cognitive schemas) rather than taxonomical structures. Situating them as cultural schemas means that they are inherently flexible and adaptable. I believe we can create schematic or phenomenological ontologies for information systems using sets of tags and folksonomies, which can complement and supplement the formal ontologies that are developed by ontology engineers and information scientists.

So, that’s my thesis and proposal in a nutshell. Although I try to explain it as simply as I can, most people still have trouble grasping it. I consider myself very lucky to have a committee that gets it. And each brings a particular expertise to the committee that touches on the major components of my justification and research project. I’m really excited and looking forward to June 12th.

Tags:cultural schemas, culture, folksonomies, Heidegger, ontologies, ontology, semantics tags
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Re-blogged from Autism and Understanding Others « Neuroanthropology

Amanda Baggs presents her own life and thoughts in her YouTube video, In My Language, her translation of how she is in a constant conversation with the world around her.  She is autistic and does not speak.  But she can type, and after three minutes showing her interacting with her environment, she uses computer technology to explain herself to us.

This is interesting to me because it provides a high contrast example of the difficulty of communication between cultures. It is difficult for many people, even academics, to grasp the idea that culture has a significant impact on what we perceive as real and existential. People from different cultures don’t see the same things, even when looking at the same entity. When walking through the Australian Outback, I come across a rock formation and I see it as a rock formation. When one of the indigenous persons of the area come across that same rock formation, they see it as Krantjirinja, their Kangaroo Ancestor. It’s not a “different interpretation” or differing “social constructions” that apply different words to the same entity. They are not the same entities.

Such is the case with Amanda Baggs. She perceives a completely different world, understands and communicates with and within it in completely different ways than non-autistic persons. Not understanding what she experiences during the first three minutes of the video–having no reference system with which to understand it–makes it frustrating for those of us who are used to a particular form of cultural interaction. If we give in to our frustration, we dismiss Amanda and pass up an opportunity to expand our cognitive horizons and understanding of the world (and the autistic persons in it). Amanda’s video is an extreme example, but we often don’t invest enough time to understand before dismissing people from other cultures or simply assuming that they see what we see.

The problem is the same for computational systems, especially across domains. Creating a “specification of a conceptualization” will never be able to address the issue of seeing completely different things, even if it is machine-readable. It’s difficult enough to construct an ontology for a single domain, but trying to do it across domains requires a completely different approach. Machine-readable specifications just wont’ cut it. It’s like trying to give a dictionary or a glossary to someone and telling them to learn to speak another language.

This is why I advocate for the introduction of culture into the study of ontologies in computational systems. Ontology is, after all, a philosophia prima that examines the notion of Being, explores the nature of existence and tries to describe what exists. But there are many ways to understand the nature of existence, and culture is the primary force in shaping our understanding of it. So if we are to be successful in developing ontologies for our information systems, we will have to incorporate an understanding of the culture that uses the technology and the information within the system. Only then will we be able to see what members of other cultures see and be able to translate information meaningfully.

Tags:cultural schemas, culture, ontology, perception, semantics understanding
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[This is not meant to be a well-written, coherent essay. Rather, it is simply my reflections of some of the concepts discussed in: Uschold, M. (2003) Where Are the Semantics in the Semantic Web? AI Magazine 24(3): 25-36.]

Talking about an agent’s ontology, Uschold says:

If it were written only for people to understand, this specification could be a glossary.

It is a simple statement that belies the complexity of human cognition and its ability to function as a connectionist network. Humans are able to read a word and its definition and recall a complex of associations and experiences to create meaning, to understand its semantic content and the ontological commitments that are shared within a community. An agent doesn’t have this ability and must rely on explicit specifications (ala Gruber) and formal languages to communicate its meaning to other agents. Successful communication is the goal, but machines are confronted with heterogeneous sources, “different ontology representation languages, different modeling styles, and an inconsistent use of terminology.”

Uschold describes the semantic continuum:

Semantics can be implicit, existing only in the minds of the humans who communicate and build web applications. They can also be explicit and informal, or they can be formal. The further I move along the continuum, the less ambiguity there is, and the more likely it is to have interoperable, robust, and correctly functioning web applications.

The difficulty with implicit semantics is their inherent ambiguity. People don’t always agree about the meaning of a term. Yet this is exactly where people live, so to speak. Humans engage in dialogue and discourse in order to clarify meaning. Through this interaction, we make the implicit semantics explicit. Engaging with machines isn’t as interactive, typically. We don’t expect our machines to be intelligent in terms of understanding semantic content and to be able to express that understanding as humans do. We also don’t expect that machines will be able to assess contextual cues that we use as humans to make meaning of our interactions with others, nor do we expect machines to remember our previous interactions with them (unless we explicitly encode that into the preferences of each particular application or service).

As Uschold continues to describe the continuum, moving towards the more formally expressed semantics for machine processing, it occurs to me that what we are doing is conforming our natural ways of interacting to the requirements of a machine. Why are we not trying to make the machine conform to our natural way of doing things? Shouldn’t the goal be to enable the machine to dynamically discover the meaning of content and how to use it? This, as it turns out, is what Uschold tackles next, machine-proccessible semantics:

For a computer to automatically determine the intended meaning of a given term in an ontology is an impossible task, in principle; it would require seeing into the mind of the author. Therefore, a computer cannot determine whether the intended meaning of two terms is the same.

Getting an agent to understand semantic content can be accomplished by hardwiring the meaning of terms and procedures into them, or through accessing external, publicly agreed to declarations such as ontologies. The heterogeneity of information and meaning makes both of these strategies limited. Information from different web sites may need to be integrated, so we require some way to map the different meanings to each other. Ontologies in conjunction with semantic mapping and translation techniques play a key role in semantic integration (Uschold citing Bradshaw et al. 2003).

Uschold speaks of human consensus regarding the use of terms. He refers to this consensus as an implicit shared semantic repository. I use the term cultural schemas to refer to this shared cognitive “repository.”

So, where are the semantics in the semantic web? Uschold offers these six explanations:

1. They are often just in the human-as-unstated assumptions derived from implicit consensus (e.g., price on a travle or bookseller web site).
2. They are informal specification documents, e.g., the semantics of UML or RDF SCHEMA.
3. They are hardwired in implemented code (e.g., in UML and RDF tools and in web shopping agents).
4. They are in formal specifications to help humans understand or write code (e.g., a modal logic specification of meaning of inform in an agent communication language).
5. They are formally encoded for machine processing, (e.g., fuel-pump has (superclasses SHO: pump)).
6. They are in the axiomatic and model-theoretic semantics of representation languages (e.g., the formal semantics of RDF).

Tags:cognition, concepts, cultural schemas, formal ontology, information, language, ontologies, semantics semantic web
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Explaining what ontology is is difficult enough. Everyone seems to have their own idea about what it is. I have my own ideas about what ontology is and how they should be constructed. Even more difficult is trying to explain what an ontologist does. The Preface to the FOIS’06 Proceedings crafts an extraordinary description of ontology and the work of ontologists as theoreticians and engineers.

Formal Ontology in Information Systems, Proceedings of the Fourth International Conference (FOIS 2006), Brandon Bennett and Christiane Fellbaum (eds.), IOS Press

Preface

Since ancient times, ontology, the analysis and categorisation of what exists, has been fundamental to philosophical enquiry. But, until recently, ontology has been seen as an abstract, purely theoretical discipline, far removed from the practical applications of science. However, with the increasing use of sophisticated computerised information systems, solving problems of an ontological nature is now key to the effective use of technologies supporting a wide range of human activities. The ship of Theseus and the tail of Tibbles the cat are no longer merely amusing puzzles. We employ databases and software applications to deal with everything from ships and ship building to anatomy and amputations. When we design a computer to take stock of a ship yard or check that all goes well at the veterinary hospital, we need to ensure that our system operates in a consistent and reliable way even when manipulating information that involves subtle issues of semantics and identity. So, whereas ontologists may once have shied away from practical problems, now the practicalities of achieving cohesion in an information-based society demand that attention must be paid to ontology.

Researchers in such areas as artificial intelligence, formal and computational linguistics, biomedical informatics, conceptual modeling, knowledge engineering and information retrieval have come to realise that a solid foundation for their research calls for serious work in ontology, understood as a general theory of the types of entities and relations that make up their respective domains of inquiry. In all these areas, attention is now being focused on the content of information rather than on just the formats and languages used to represent information. The clearest example of this development is provided by the many initiatives growing up around the project of the Semantic Web. And, as the need for integrating research in these different fields arises, so does the realisation that strong principles for building well-founded ontologies might provide significant advantages over ad hoc, case-based solutions. The tools of formal ontology address precisely these needs, but a real effort is required in order to apply such philosophical tools to the domain of information systems. Reciprocally, research in the information sciences raises specific ontological questions which call for further philosophical investigations.

Tags:concepts, fois, formal ontology, informatics, information, language, ontologies, philosophy, science semantics
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I recently attended the Vespucci Initiative’s summer institute on geographic information science. It was held from 3-7 July 2006 outside of Florence, Italy. I’d never been to Italy before, and I had a fantastic time. It was my first foray into my own academic community, meeting with people who are doing research related to my own. I established a number of contacts with other graduate students, some of whom I hope to collaborate with in the future.

I got to share a lot of my ideas on the creation of ontologies for geographic information systems. My ideas are pretty radical and unlike the approach most ontology engineers take. I was a bit scared that people would think me insane, but the opposite turned out to be true. I was able to explain the complexity of my reasoning to academics as well as industry folks. They were intrigued by my ideas and my approach, so I came away from the workshop feeling pretty good about the work I’ve been doing over this last year. Of course, there are several more pieces of the puzzle that I have to work out, but I’m confident that I can contribute to the research and development of ontologies in information systems.

Firenze and Fiesole were beautiful. I didn’t care too much for the crowds in the city, and it was hot as hell, but being immersed in such an historic city and the Italian food and culture compensated. I did take a few pics, including some of il Duomo. I’d love to go back to Italy at some point and explore some other cities, like Venice, Genoa, and maybe even Rome.

Tags:fiesole, florence, geospatial, gis, italy, ontologies, sdi, semantics, tuscany vespucci
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