April 13th, 2007

Hans Rosling / gapminder


Watch Myths about the developing world, a talk by Hans Rosling from gapminder.org Intense, thrilling, passionate. 10/10.

April 11th, 2007

Innovationsforum Interaktionsdesign: a late review


Although finished already over a week ago, some words on the Innovationsforum Interaktionsdesign organized by the Interface Design Program at FH Potsdam (where I happen to study). To put it short: It was a blast!

Especially remarkable:

• The design concept of the conference itself: excellently conceived and executed with love to detail. See monomo for some pictures. Props and respect to formdusche

• The line-up was really impressive – find complete coverage of the talks at wmmna. Lots of pictures also on flickr, especially James King’s scribbled coverage of some of the talks — here’s the one of the 10 minute talk I gave together with Fabian at the student’s panel: jameskinginnoforum.gif

• Bruce Sterling’s talk was, as expected, “something completely different” and he really hit the nail on the head a couple of times:

Never thinking about it again is the ideal relationship of a normal human being and an object. That is the opposite of how designers think. I realized this when I was teaching at Art Center College of Design. My students were doing media design, some of them, and very commonly they would come out with some gizmo on a neck pendant. “See, the user wears this large device dangling around his neck, and…” “No,” I would tell them, “your design project is not hung around the user’s neck. The user has other uses for his neck. This project is hung around YOUR neck. You’re the designer, you’re the one who has to obsess about the device, not them.” You obsess MORE. Let them obsess LESS.

Read Shaping Things if you haven’t yet.

Other than that, Anthony Dunne, Bernard Kerr and Tim Edler really impressed me.

An inspiring event, I wish we could have that every year!

March 11th, 2007

Elastic lists

Just a short post, but another demo is online.


It is a demonstration of the “elastic list” principle for browsing multi-facetted data structures. Click any number of list entries to query the database for a combination of the selected attributes. If you create an “impossible” configuration, your selection will be reduced until a match is possible.

The example data is based on the Noble prize winners dataset used in the Flamenco facet browser.

Elastic lists enhance traditional facet browsing approaches by • visualizing relative proportions (weights) of metadata values by size • visualizing unusualness of a metadata weight by brightness • and animated filtering transitions.

In unfiltered view, the brightness shows a trend measure, indicating a rising number of prices of the last years.

In filtered views, a brighter background indicates a higher weight of the metadata value compared to the overall distribution.


If, for instance, you click “peace” as in the example above, you will see that “female” and “Switzerland” are much brighter, indicating that the proportion of women and Swiss is much higher in this context than compared to the whole data set. That’s interesting information and could also be used to characterize the result set of a keyword query or any other collection in terms of its “characteristic” metadata values. Besides that, it fosters understanding of how metadata values are correlated with each other, which is often interesting information itself.

You can also switch on little sparklines to see the temporal distribution of each metadata value: picture-7.png

February 19th, 2007

Emerging topics v2

I am currently working on trends in individual tagging behaviour. You might have seen a first, animated version of my studies based on tag maps. The original animation shows the emergence of previously rarely used tags over time. Now I dug deeper and made a richer visualization for investigating this topic.

For the impatient: » Check out the interactive version here

And here’s the explanation:

It has been shown before (for a plausibility argument, also check out the marvellous cloudalicious tool, where you can track tag proportions for any website on the web), that tag proportions for ressources stabilize over time. Which means that the tag cloud representing a tag profile for a resource does not change much, once a sufficient number of tags has been collected. In a folksonomy, this is generally considered a good sign, since this indicates a certain agreement on how to judge a certain ressource and what vocabulary to use.

For tagging individuals, and communities, this might — at first glance — hold true as well. Consider the following the visualization of a tagging community‘s evolution, for example:


Each tag is assigned a band, with the thickness indicating the overall summed usage of a tag over time (time runs left to right). Thus, a vertical cut through the graph corresponds to taking a tag cloud snapshot at this time point. The vertical order is based on the overall frequency of the tags. The color is used to to give an impression of the long tail distortion – if all tags would appear equally often, you would see a linear transition from red to green instead of the skewed distribution. So – what do we see? Apparently, most of the bands seem to grow in parallel, indicating a stable growth proportion for all tags. Of course, we cannot see much for the smaller tags, and there are some edgy parts of the graph which might indicate different behavior at specific time points, but overall – pretty stable impression.

However, this does not make much sense. For individuals and communities, the topics of interest evolve over time, so there must be some hidden variability not captured by the visualization and the underlying linear model.

So I decided to provide an alternative visualization for the data based on a decay model, where tags “age” over time and finally get “forgotten” if they are not used anymore. This idea is loosely based on the Yules-Simon memory model for tag generation presented in this paper.

picture-7_480×266shkl.png A radically different picture emerges. Not only does the overall shape now nicely display phases of community activity over time, but also the life cycle of single tags is much more transparent. You can rollover single layers highlight it and display the corresponding tag name. Great fun.

» Check out the interactive version here

What I am now curious about: – Is there a correlation between time-dependency and over-all frequency of tags? In other words, are frequent tags more evely distributed over time, whilst the low frequency tags tend to be more variable over time? – Is there a correlation between temporal synchronization and general co-occurrence? Which means – do related tags also appear and disappear together over time?

I think the answer is YES to both questions, but that would definitely need some statistical analysis (any bored neuroscientists around to help me? ;)

To-dos for the visualization: – Implement a slider, so you can see how a linear and decayed tag cloud would have looked like at a specific time point. – Stamen got it right: Maybe I should have plotted from the vertical center. Or at least provide an optional inversion of the sorting. Because right now, all the top (green) layers are really distorted, making visual analysis really hard. – Put some numbers on the axis – Show single tagging events on rollover. Or even “unfold” the layer to improve readability and avoid misconceptions.

February 7th, 2007


I have been subscribed to the indexed blog for a couple of weeks now and really, it never ceases to amaze me. Hands down, this is one of the most funny, original and yet deepest blogs I have seen.

The concept is simple: little stories or facts about life are told with infographics drawn on index cards (which I love anyways). Its amazing how much laughs or “true, true”s you can get out of little Venn or axis diagrams:


Reminds me also of the wonderful Facts of life by Pippo Lionni.

Comments Off on Indexed  
January 31st, 2007

Quantitative data visualization

Recently, a number of interesting online tools for quantitative data visualization popped up:


“…is a place where curious people explore all kinds of data.” (tag line) It allows anybody to upload, visualize and share data sets. The diagrams can be embedded in any web page by using HTML snippets. I haven’t figured out yet if these update automatically, when the data set changes. If so, this is a really neat way to display dynamic graphs on your page. And the whole sharing/discussing data aspect is really interesting.

Concerned About Calories?



My favorite online web site analytics tool, which I totally forgot about, because it has been offline for two years or so. But the relaunch was really worth the wait, nice style, except for the glossy buttons (WHY?), the colors and visual ideas are really good. Also feature-wise, it easily puts google analytics behind – trend analysis with polynomial fitting, real-time analysis, in-depth stats etc. I recommend testing it out if you are a stats junkie as I am.

IBM: many eyes

Looks a lot like swivel, except there are far more visualization options and the diagrams are interactive (Java though – hrrr). Haven’t looked at it in depth yet, but it looks very interesting as well.

January 31st, 2007

Husserl and tagging

A very nice paper on the “laissez-faire librarianship” often associated with tagging vs. more structured semantic web approaches. Most notable is that the discussion is put in the context of Husserl’s theory of reflections, intentionality and intersubjectivity.


D. Grant Campbell Faculty of Information and Media Studies University of Western Ontario
London, Ontario N6A 5B7, Canada

Abstract This paper uses Husserl’s theory of phenomenology to provide a model for the relationship between user-centered tagging systems, such as del.icio.us, and the more highly structured systems of the Semantic Web. Using three aspects of phenomenological theory—the movement of the mind out towards an entity and then back in an act of reflection, multiplicities within unity, and the sharing of intentionalities within a community—the discussion suggests that both tagging systems and the Semantic Web foster an intersubjective domain for the sharing and use of information resources. The Semantic Web, however, resembles traditional library systems, in that it relies for this intersubjective domain on the conscious implementation of domain-centered standards which are then encoded for machine processing, while tagging systems work on implied principles of emergence.

January 22nd, 2007

Tag maps update

As promised, here is an update to the tag maps application I introduced below along with some explanations.


For the impatient: HERE’S THE LINK

(Update again: The latest version can be found here)

And for the curious: Here’s the explanations: → read more

January 11th, 2007

Personal network search

For my thesis, I am working on interfaces for the socio-semantic web. How can we exchange structured information snippets (“microcontent”) and metadata in small communication cliques via RSS – and what interfaces do we need for that?

One really hot perspective here is the search for information from a network of trusted sources, and this is exactly what the people at Stanley James’ company lijit do. They provide you with a personalized search engine, which returns google results only from

  • – your own published information (via your blog, public bookmarking tools, flickr, photo sharing, etc.)
  • – plus information published or marked as “good” from people you trust

So in a nutshell, you can search your own network (“What have people I know bookmarked or published about the new iPhone?”) or other people’s networks (“Stan is the expert on social networks – let’s see what he and his friends have bookmarked or published about it.”)

This is definitely quite stimulating. It still has to turn out in which situations a personal network search is far superior to the global web search or a personal, local search on my own resources and if people will adopt it. But I have the strong intuition that they are filling a huge gap here: connecting people and contents on web scale independent of individual bookmarking or publishing tools. This is kind of a meta-service for what comes after Web 2.0.

You can try searching my network here:

Lijit Search