David Davies' Weblog

I think we're getting close to something big, very big. The European Space Agency's Mars Express probe has confirmed earlier findings that the Martian atmosphere contains traces of methane. Apparently there are only two plausible sources of methane in a planet's atmosphere, volcanic activity and biological processes. What's more, as methane only persists in the atmosphere for a relatively short period, it must be being constantly replenished. As Mars seems to be devoid of any obvious volcanic activity, well, draw your own conclusions, at least until someone sends up another probe with a methane sniffer on board. Ironically, the doomed Beagle 2 probe had such an instrument on board. Perhaps the Martians knew we were getting too close.

I've updated the Comment watcher tool to now produce two bookmarklets, one for Apple Safari and one for all other browsers. Please let me know if these work for you.

If you're installing my new Comment Watcher tool there may be an issue installing the bookmarklet depending upon whether you're using a Mac or PC web browser. I'm on the case and will post an updated version later this evening.

Head's up, Gia's got a new showreel. Watch, enjoy, employ :)

I've put together a simple tool for Radio Userland weblog owners that allows them to track comments on other people's weblogs. Basically, the tool uses a bookmarklet to capture the URL of a weblog comment window, subscribes to it and checks it every hour. If the comment thread has been updated since the last check you get a notification email. Simple as that.

This first version is pretty basic but seems to work. The next version will be a little more sophisticated and I'll try to incorporate comments/suggestions from users. I also have a Manila version if anyone's interested.

Get your copy of the tool here. Probably best to right-click and save the link to disk. Put it in the 'Tools' folder in your Radio application folder. Once you've downloaded the tool and put it in the right folder, you access it's home page here:

http://127.0.0.1:5335/commentwatcher/

Full instructions are contained on the tools' web pages. Usual caveats, this is a work in progress. Let me know how you get on.

I've declared in several places that I find it difficult to keep track of weblog comments I've made, and the conversations that arise as a result. In fact I've even lost track of the places where I've declared that, case in point!

So I've created a tool for Radio Userland and Manila weblogs that allows you to keep track of all the weblog comment threads you're interested in, whether you've contributed or not. This tool is currently working for me so I'm fast approaching the time when I'd like to release a version out into the community to see how it works for others. If you'd like to try out the first release please let me know. Once I've had a couple of people test it for obvious bugs I'll release a public version for anyone to try. Please get in touch if you'd like to try out the pre-release version.

Comments about how you'd like such a tool to work are also welcome. Presently, without giving too much away, the tool alerts you via email if a particular comment thread on any weblog is updated, regardless of the platform or blogging/comment software.

John Gruber has written an interesting piece on, amongst other issues covered, markdown. Markdown is the opposite of markup (cf. HTML markup) and attempts to reclaim readability and simplicity in weblog post by eschewing non-essential HTML tags. I can identify with a lot of what John says in his post but with my own posts there are a couple of areas where I feel I must use HTML markup, so this got me thinking about my own weblogging work flow.

I used to type directly into the edit box for a new post. As I'm on a Mac I can't use the clever WYSIWYG editor features that come with my weblogging software (those features are Windows only) so any HTML I want to include in my post I had to add manually. This got to be too much of a pain, so in that respect I can totally sympathise with John's markdown principle. But then I discovered the joys of using a stand-alone WYSIWYG HTML editor, specifically Adobe GoLive. This application takes all of the headache out of writing a post and allows for simultaneous write/edit/preview.

Now here's the bit of my own work flow that'd be just too darned tedious to do by hand, embedded images and links. I tend to use a lot of these and to do them properly e.g. add ALT tags to images and assign titles to links is just too time consuming without an editor. Now, with the exception of posts sent straight from my mobile phone, I try to correctly use ALT tags and link titles as I think it provides a better reading experience and is probably more compliant in terms of accessability.

Lastly, I noticed another advantage of writing in a stand-alone HTML editor such as GoLive. If I want to write about writing HTML i.e. include HTML tags in my posts as part of an illustrative code listing for example, then this is all taken care of for me as GoLive automatically converts the tags I write in WYSIWYG mode into encoded tags. For example, <br> in WYSIWYG mode becomes <br> in source mode and therefore doesn't confuse the browser.

Taken together with other useful editor features such as spell checking and a drag-and-drop library of HTML objects, I'm very happy with my present work flow.

Great Kraftwerk gig at the Manchester Apollo last night. Read all about it here.

Carrying on from comments the other day about what metadata is useful, I'd like to make a distinction between metadata that I as a human would find useful (title, description, URL etc.) and what metadata a computer would find useful, particularly a computer running an intelligent tutoring system. To make this distinction I'll introduce what I call learning object processors. A learning object processor is an intelligent tutoring system or ITS (for want of a better term) that knows how to assemble learning objects into something useful for an individual or group of individuals. The ITS uses assembly rules to select learning objects and put them together, or aggregate them in the parlance du jour, pretty much like a software compiler uses rules to assemble source code into an executable computer program.

An example of an ITS would be a software program that can assemble learning objects to present a simulated medical patient case. A student is presented with a scenario representing a real-life patient with, oh, let's say diabetes. The simulated patient case includes a video of the diabetic patient talking about his/her illness, background reading about the subject, various clinical investigations being undertaken along with a presentation of their result, you get the idea. The student uses this simulated patient case to learn about real-life patients with diabetes, or just about any other medical condition you could think of. Now imagine a situation where for whatever reason, say, cultural convention, we can't show a simulated patient case of a woman, so we must present a case with a male patient. We could manually rebuild the case using data from a male patient, or we could use an ITS that knows how to swap in and out the components of individual cases. This ITS could automatically select replacement data for our student and reassemble a new case to meet the cultural requirements. The use of different languages would be another example where alternate content would be required.

In order for an ITS to perform its data swapping exercise in anything like an automated way, it'd need to know how to find, select, and incorporate new learning objects into the patient case. It would use metadata to perform this magic. These metadata would describe objects in a repository that have the required 'fit' and can act as alternative information blocks in our hypothetical simulated patient case. The metadata required to describe a component such as I have described are very different from the metadata that I as a human would find useful when searching for information about diabetes in our example. It may be stretching the computer program analogy too far but I'd say that the metadata used to define the hot-swappable learning object components would be more like the sub-routines in a program's source code listing. Each sub-routine has its input and output parameters, and when plugged into a larger program in the correct way performs an essential function. Well-written sub-routines from other people could just as easily substitute from my sub-routines, such that with an appropriately diverse bank of sub-routines I wouldn't need to write very much of my own code at all, I could just assemble code provided by others, topped off with a bit of linking code to make it work the way I liked.

There's only one problem with this metadata scenario, the kinds of metadata present in the LOM are not the kinds of metadata we'd need to make this ITS work, and this simple ITS described here is only one of thousands of potential ITS', each fulfilling specific high-level learning needs. So what we really need are working groups within subject domains scoping out how they want their intelligent tutoring systems to function, and to start agreeing on ways of describing learning objects to allow them to fit together in meaningful ways. Metadata can mean different things to man and machine, and one size will not fit all. We have lots of metadata we could be using, let's try to agree on the metadata we should be using and start using e-learning in interesting ways.

What would be on your list of things that every new teacher should know about e-learning? Ideas are for an upcomming published piece so a name check for useful suggestions.

Up to now I've tried to steer clear of the whole 'what are weblogs' debate. I think it's a futile question. They are whatever the owners of weblogs choose to make them. What is television? Same futile question.

There is a lot of talk lately of social software. Exactly what social software is I still don't know. But as people are fundamentally social people it must be important. I have a suspicion that what most people are talking about when they talk about social software are contact managers. Glorified online address books where I share my contacts with you and vice versa in the hope at least one of us meets new and interesting people as a result.

These days I tend to meet new and interesting people on the web by reading their weblogs (I have a life outside of the computer where I use different - though not fundamentally so - strategies for meeting new and interesting people). I find new weblogs via all kinds of routes such as links, trackbacks and comments to my own weblog (an ice-breaker for sure as we must have had something in common to have established the link) or via similar links on weblogs I already read. In one sense therefore I am already a participant in a social network, the network that extends around my weblog and those weblogs I read often. As a result of the nature of the web, and the rapid take-up of weblogging as a form of personal expression, this network is ever-expanding.

This social network is richer than any I could attempt to create intentionally. By reading a person's weblog I can get so much more understanding about them as a person than I ever could by using so-called social software, where an individual is reduced to a thumbs up or thumbs down icon plus ancillary information such as place of birth, pet's name and favourite colour. Like Lilia, I think weblogs are conversational tools. Sometimes you may be having a conversation with yourself, other times you're part of an exciting group discussion, but either way you're part of a social network that surpasses any that existed before weblogs.

So, despite my reluctance to enter the 'what are weblogs' debate, I'm going to stick my neck out and say that weblogs are the social infrastructure of the Internet.

Just in case you haven't discovered Lilia Efimova's weblog, please take time to pop across and read one of the most interesting sites in the present blogosphere. Lilia writes intelligently on many topics and is currently exploring the nature of weblog conversations. I've always been frustrated by the lack of tools to track conversations across multiple weblogs, and in particular weblog comments. Sometimes I use web browser bookmarks, sometimes I can use my RSS aggregator, but often it's just a real pain. As a consequence I am doubtlessly missing out on lots of interesting discussion. Perhaps Lilia's research will come up with some interesting recommendations for the makers of weblogging software. In the meantime, if anyone has any tips for tracking conversations, then please feel free to start a new conversation on this weblog.

Alan wants to know why anyone would want to use metadata. Well, speaking as someone who thinks the LOM is a solution to a problem nobody really has, I'm not the best person to reply. However, I do find some metadata to be very useful. I think for many applications you can get away with knowing 5 things about a resource:

1. Title. Because everything has a name, right? That's what we do, we label things.
2. Description. Because I want to know a little bit about your resource, especially if your resource is one of many in a list of search results.
3. URL. I need to be able to find your resource. Perhaps this should be 'location' rather than just URL because some of us still use stuff that's not on the web (really, some still do).
4. Controlled vocabulary keyword(s). I need to know that when I say potato, you say potato, and when you say tomato, I say tomato.
5. Copyright statement. Because very often you don't own the thing you created, your institution does, and I'll need to know who I have to ask to use your resource. And when you do own your resource, I need to know that, too.

I think you can do a lot with these data. "Like what?" Alan might ask. Well, for me, there's really no point using any metadata unless you intend to share your resources. If you've got 3 resources to share, just give them to me and be done with it. If you've got more, these basic pieces of data that describe your resource will probably help me find them when I search a database. A controlled vocabulary keyword would help me find you resource more effectively (especially if you give your resources non-descriptive titles and don't use the same words that I'd use to describe the resource). The copyright statement is just good manners as it makes it easier for me to work out who I need to ask to use your resource.

The first 3 fields in my list or 5 fit nicely with RSS and are the kinds of metadata that are so common we'd hardly even think of them as metadata. The copyright statement is something that's also pretty straightforward, or at least it's something that we understand to be important. Although many people don't understand who owns the resource. The only difficult think is keyword(s). These can be optional of course though searches are much more accurate when they're used. And using a controlled vocabulary to assign your keywords saves so much confusion. Pity there are so few agreed controlled vocabularies.

As for Alan's other question about why use OAI, I can't think of a convincing answer. Although I do know that one of the goals of using OAI is the ability to exchange metadata records rather than the object itself, which makes sense from a bandwidth point of view. I think an RSS aggregator approach would be just as effective, not least because RSS aggregators are easy to use and readily available. If you used RSS 1.0 then you could even use Dublin Core module to include the copyright and keyword fields in your feed.

Update: Just watching NASA TV now. Well, it's exciting but not the big news that some were speculating. The Opportunity team have found conclusive proof that layered rocks seen on the day Opportunity landed were indeed laid down in a very wet environment. So there was water on Mars millions of years ago. I guess we'll have to wait for the next press release to hear about Martians.

At 2pm EST today NASA will issue a press briefing during which it intends to announce significant findings about Mars. These findings come as a result of the ongoing success of its two rovers, Spirit and Opportunity. The word on the street is that the significant finding will be about evidence of past water on Mars. What would be really exciting would be some evidence of current water, realistically not as the freely flowing sort we know and love here on Earth, but perhaps as very salty brines intermingled with the Martian soil. However, where there's water there's a chance for life. Perhaps 'significant' could even mean... no, it couldn't... could it?