Ok, I admit it. I'm a gadget freak and a visualization freak. So of course I am going to enjoy playing with the Google Visualization Gadgets. You need to check periodically to see what cool gadgets Google or 3rd party developers might have added to the gallery. Today I notice a new Treemap gadget by DrasticData. I was present at CHI99 when Wattenberg first showed this visualization which became famous as the "Map of the Market" on SmartMoney. It is great to see a high-quality implementation arrive which can work with the Google Vis API.

This visualization works really well for a dataset with lots of members and which also has some grouping. The grouping turns the data into a two level tree or hierarchy. A good test therefore is this query:

SELECT
  METRICS ga:visits,ga:pageviews,ga:entrances ON COLUMNS
  DIMENSIONS ga:browserVersion,ga:browser ON ROWS TOP 100 BY ga:visits
FROM [www.shufflepoint.com]
WHERE TIMEFRAME yearToDate

Browser Version is the leaf level data and Browser is the grouping. A screenshot is shown below.

Link to live demo

References

Google Visualization API Gallery

http://code.google.com/apis/visualization/documentation/gallery.html

Google Visualization API Reference

http://code.google.com/apis/visualization/documentation/reference.html

Visualization: DrasticTreemap

http://www.drasticdata.nl/DrasticTreemapGApi/index.html

Wikipedia entry on Treemap

http://en.wikipedia.org/wiki/Treemap

Visualizing the stock market (Martin Wattenberg) - CHI '99 abstract

http://portal.acm.org/citation.cfm?id=632834

Martin Wattenberg CHI '99 paper

http://www.research.ibm.com/visual/papers/marketmap-wattenberg.pdf