Categories
RDF

Browser Dux or Deus or Duck?

In comments Dylan writes about having a visual RDF browser, …it would seem that a RDF Browser would be useful in traversing different distributed data as you follow connections and learn new information.. Danny Ayers also responded with:

If I have your Poet Vocabulary plugin for my browser, whenever I encounter material containing appropriate terms from that vocab those parts of the screen will go sepia-tinted and slightly out of focus.

I rather like that myself. Except not out of focus, let’s have the words pulse, as if they’re the beat of a heart of a new born bird. Or some such thing.

Sigh. How semantical.

They both do have a good point if you consider the visual tools that have been available for relational data models for years. I can’t remember the first tool I used, but the modeling technique was known as IDEF0, following an Air Force requirement.

In this technique, independent data objects were square cornered, but dependent objects were curved. Arrows were drawn to represent the relationships between the objects, and the key columns were highlighted above a solid line within the boxes. Categories had a circle above a couple of bars.

Models allowed us to look at the data and its relationships with each other, and helped us identify dependencies, as well as missing data. Typically, we would define the model to a particular normalized form, and then denormalize it for performance. In both cases, we’d create data models so that we could show a mapping for this conversion.

A key difference, though, between RDF and relational data, is that the meta-data to drive a data model is included with the data itself, so a model could actually be automatically generated from the same database that contained the data. RDF, on the other hand, doesn’t necessarily provide the meta information included within the same source as the data. The RDF namespace should have a defined schema, and this schema should provide this meta information – but there’s no guarantee this is accessible.

Still, as BrownSauce demonstrates, much about the model can be defined from what can be found, and if there’s enough to display nicely as HTML, there’s no reason that we can’t draw a bubble. Or a box, if we’re so inclined. But then that gets us back to my original question: would we want to?

One of the keys to understanding the RDF data is to have good text definitions to go with the objects so that we know what the data is all about. Unlike with our IDEF0 efforts, when we had a fairly good idea of the business context, an RDF/XML file (or other format if you’re a picky purist) is out there on the web, just hanging around and if you don’t know the context (i.e. “This is my FOAF file”), you need good definitions associated with the objects. A visual model won’t help with this, thought BrownSauce, with its text extrapolation is very helpful.

But there are those times when we start looking at merging data from the same or even dissimilar schemas, where a visualization could be a handy bugger. But it’s also much tricker than IDEF0. You see, a IDEF0 model has a basic functionality and purpose and the relationships between objects are very well known. The same can’t be said about any relationships between data discovered out on the web.

It’s not that the visualization can’t be done, but when it is done, it may not add value or useful information. Somewhat like a FOAF file for a person who claims five hundred people as close, personal friends – visualizing this, even to one or two levels will be impossible, and meaningless.

Probably about as meaningless as a friendship with someone who can claim 500 friends…and counting.

However, it could be a fun project, with interesting results. I’m always up for new toys. So who’s going to do it?

Categories
outdoors People Photography Places

Fighting Failure

All indications say that the fall colors this year will be muted compared to last year. I can see this already when I go out for a walk — too many leaves just dying without that final burst of color, falling to the ground as damp, dark shapeless lumps. But it’s still a bit early in the season for Missouri, so I have hopes.

I thought the monarch butterflies might be out and visited Shaw today to get butterfly pictures, but most of the flowers had already started to fade and the butterflies mostly gone. However, I was exceptionally lucky to have spotted some of the brilliantly colored prairie gentian. Or at least, I think it’s the prairie gentian. Whatever it is, it’s a lovely, delicate, beautifully colored flower–a rara avis in the plant world.

Though I could find no butterflies, there were caterpillars out and about, and I had to keep a sharp eye out when driving to not run over any. When I was walking around the lake, I saw one fine, fat fellow walking down the exact center of the road — not from side to side, like others I’d seen; right down the middle, as if he hadn’t a care in the world.

He was crawling fast, too, and I had a hard time getting his photo without too much motion blur in the background. But then, motion blur with a caterpillar works, don’t you think? Like a cosmic giggle.

I left my fair butterfly-to-be and tried the prairie near the visitor center in hopes of spotting one monarch, but the most I saw were bees, more bees, and some other odds and ends of flowers on their last legs. I was extremely pleased to see that I’ve lost most of my phobia of bees and can now walk among them without fear; a few years back, I’d have run screaming from the area. But I’ve been bitten by so many things this year, a bee sting would have all the familiarity of an old friend who says painful things for your own good.

(For instance, this last week I received two identical bites, one on my upper back, right in the middle; the other under my bra on my right side. Not ticks, because the little bite marks are too big. Who knows what got me this time, it’s becoming a running joke in my home, “Eh, I’m off to feed the critters, again.” My roommate estimates that I’ve become an important part of the Missouri ecosystem. It’s reassuring to know that, no matter what else, one is always good enough for the bugs.)

When faced with the nothingness of the butterfly garden filled with bees, I was reminded of my enthusiasm with existentialism lately and my wonderful new discovery that Jean-Paul Sartre wanted to write a cookbook. Yes, indeed, he was the ultimate foodie, I kid you not. Following is an entry in his diary, which provides a recipe for tuna casserole ala void:

October 10

I find myself trying ever more radical interpretations of traditional dishes, in an effort to somehow express the void I feel so acutely. Today I tried this recipe:

Tuna Casserole

Ingredients: 1 large casserole dish

Place the casserole dish in a cold oven. Place a chair facing the oven and sit in it forever. Think about how hungry you are. When night falls, do not turn on the light.

While a void is expressed in this recipe, I am struck by its inapplicability to the bourgeois lifestyle. How can the eater recognize that the food denied him is a tuna casserole and not some other dish? I am becoming more and more frustrated.

When you are an artist, how frustrating, indeed, to deal with those who lack the discernment to see that the emptiness that surrounds them is a tuna casserole; they persist in smelling goulash.

Back from the bees to the road again and my friend, the caterpillar, and it’s onward march down the exact center of the road. Moved by what, I don’t know–probably visions of tuna casserole–I put my foot in front the caterpillar, curious as to what it would do when faced with an obstacle.

It stopped dead and touched my shoe carefully, as if trying to figure out what it was. It started to crawl to the right, stopped, then crawled a little to the left. Finally, it climbed onto my shoe.

It climbed a little way forward and encountered the ridge where my sole meets the upper, and stopped again. Eventually, it followed the ridge around the shoe to the other side, but rather than get off, it just kept following the ridge, round and round my shoe. If I had not grown tired and sad for the little bug, it would probably still be circling my shoe now, on my foot under the table as I type these words.

Instead, I walked to the side of the road and among the the tall grasses, stamped on the ground with my shoe, gently, until the caterpillar fell off into the plants. It happily went on its way, I imagine to find the prairie gentian to eat.

One final entry from the Sartre cookbook:

October 25

I have been forced to abandon the project of producing an entire cookbook. Rather, I now seek a single recipe which will, by itself, embody the plight of man in a world ruled by an unfeeling God, as well as providing the eater with at least one ingredient from each of the four basic food groups. To this end, I purchased six hundred pounds of foodstuffs from the corner grocery and locked myself in the kitchen, refusing to admit anyone. After several weeks of work, I produced a recipe calling for two eggs, half a cup of flour, four tons of beef, and a leek. While this is a start, I am afraid I still have much work ahead.

Categories
RDF

And why would you want to?

Recovered from the Wayback Machine.

Danny Ayers points to Leo who says that A generic RDF browser is not possible. He further clarifies his statement that you would need a stylesheet to render the data correctly. And this means you would, according to him, need a separate stylesheet for every schema.

Danny disagrees partially, saying:

From a random snippet of RDF/XML you can still infer quite a few things – what are properties, what are classes. Barest minimum is that you know something is to be treated as a resource or as a literal. That’s infinitely more that you get with arbitrary XML alone (you may know the datatype of something thanks to a schema, but even then you won’t know what the something represents).

If you have the RDF Schema/OWL ontology for the term then you should be well away.

So why not have visual components that reflect the RDF class system

I would assume that both gentlemen are discounting BrownSauce because, technically, it shows information about objects but doesn’t necessarily render the objects visually based on some criteria or constraint.

However, it does provide a human interpretable view of the data contained in the RDF files, based on specific rules and criteria defines as part of the data model associated with RDF. But it doesn’t render anything.

Stylesheets aside, one has to ask, why would one want this in the first place? We can’t render the data in a relational database without a program providing an interface and being knowledgeable about the business model constraining the data. Yet relational data has proven itself to have a use. Or two.

Why would we want to have an RDF browser?

Leo provides a nice example of what he means by rendered RDF data, with the FOAFNaut, an online utility that allows one to query a database of FOAF data, and then depict relationships discovered in a visual manner.

Keen. Now, why would we want to have an RDF browser?

Seriously, there is nothing unique or special to RDF than there is to any other data model that has been defined in the past; whether a data is visually rendered is dependent on the data, not the general model used to define the data. Geographical data in a relational database can, and does get used for visual models; FOAF data transformed from RDF to relational could be just as compellingly displayed.

BrownSauce gives us a way to read RDF without having to understand RDF and that, to me is sufficient. Add in a little visual sugar, with bubbles and all, and that would be nice, though not essential.

But what RDF provides that a relational model does not is a way of interrelating bits of data from one model with bits of data in another model and have it make sense without having to break either model. Not just store the data together – have it work together. And does so incredibly easily by publishing simple little text files that even the most moronic bot could consume if slightly trained.

So I create my poetry schema/vocabulary and encourage people to use it to annotate their online publications that contain poems. Someone else defines a schema/vocabulary for weblog posts, capturing information such as author and CC license and category and so on, and encourages people to use it to annotate their posts. A third person comes along and defines a schema/vocabulary for web objects that captures information such as whether the object has been moved, where to, is it obsolete, or other specific types of information going way beyond HTTP status codes. This person, again, gets people to use these vocabulary.

One file is now described by three separate schemas and a bot comes along and swoops it all up and is able to combine it because of one important factor: they all identify a specific resource with a given URI.

I then come along and ask for a poem that uses a bird as metaphor for freedom and my collected data then returns a selection of posts that reference a poem, giving the name of author of the post as well as other information, such as the name of the poem and its author, the fact that the post has now been moved to that location, and there’s a photograph associated with the post.

Sigh. The beauty of it brings a tear to my eye.

But I digress, badly, from the initial conversation point: why would we want a generic RDF browser. Beats heck out of me. I’m still trying to figure out how one achieves critical mass for these three vocabularies, much less how to render them.