Stat. Graphics & Data Visualization

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This time it is easy for me, as I just need to point to the interesting discussion at Junk Charts.

The original graphics is from the NYT:

The "improved" plot looks like this:

The advantages of the box-plot view (from Junkcharts)

• The European market is much more fragmented than the U.S. market.
• The Big 2 (GM, Ford) has had mixed fortunes over this period (as indicated by the large variance)
• The Big 2 are competitive in Europe although they are definitely not dominant there
• Several key players in Europe (Peugeot, Renault, Fiat, BMW) have negligible shares in the U.S

The discussion was quite lengthy, but had the two major points:

• Boxplots are too hard to read for NYT readers
• The boxplots ignore the temporal information and thus are not really suitable for this data

One important point was not mentioned explicitly, which is

• Sorting is a very powerful and important option in graphics

There is truth to all the issues raised here, and the bottom line is probably that there might be not a single graphical view on the data which covers all aspects of the data. Furthermore, the NYT graphics is by far the most eye-pleasing version of all suggestions.

In this spirit I want to throw in two more versions which show the data:
Two variations of Mosaic Plots (will be explained in the next 'statistical graphics 101') in the multiple barchart view. European cars are highlighted:

(Year x Brand x Continent)

(Continent x Brand x Year)

 

It would be interesting to see, whether or not we could use graphics (or other statistical methods) to identify potential doping candidates ...

The only thing we would need is a list of drivers who either

• admitted doping
  
• are convicted 
• or are accused to be involved in doping. 

At least we could use the list to look at the 2005 and 2006 results to find patterns ...

Sergej did collect some data from:

• http://en.wikipedia.org/wiki/Operaci%C3%B3n_Puerto_doping_case
• http://en.wikipedia.org/wiki/Doping_at_the_Tour_de_France
• http://sports.yahoo.com/sc/news?slug=ap-tourdefrance-dropouts&prov=ap&type=lgns
• http://en.wikipedia.org/wiki/List_of_sportspeople_who_tested_positive_for_banned_substances
  

Here is what it looks like when we highlight these drivers in the 2004 classement:

There is more to look at, but for a first view pretty consistent ...

That's it for the 2007 chaos tour. Looking at the time distributions makes everybody above the median quite suspicious ... more doping cases to come - maybe including A.C.

Although many people claim little interest in the tour after the many doping cases, this is all the more a reason to check whether we will find a structural change of the 2007 race compared to the races of the years 2006 and 2005.

Stage Results	cumulative Time	Ranks
(click on the images to enlarge)

Prologue: Andreas KLÖDEN - one of the "last big ones" left - No.2
Stage 01: calm ride through the English country side ...
Stage 02: one big crash and one time for all
Stage 03: CANCELLARA defends the jersey impressively
Stage 04: HUSHOVD'S day!
Stage 05: VINOKOUROV falls back after his crash
Stage 06: Another day to rest - not only for VINOKOUROV and KLÖDEN
Stage 07: GERDEMANN aiming at white, rewarded with yellow - more than a 1-shot?
Stage 08: Nobody could stop RASMUSSEN!
Stage 09: Last stage in the Alpes and 18 drop-outs so far
Stage 10: German television stops live broadcasting after SINKEWITZ's case came up
Stage 11: VANSEVENANT 'defends' his last place successfully ...
Stage 12: A day to rest on the bike.
Stage 13: VINOKOUROV "found his legs again", at least for a day.
Stage 14: RASMUSSEN still in yellow - despite the doping case ...
Stage 15: Another stage for VINOKOUROV
Stage 16: VINOKOUROV's case end the tour for team Astana
Stage 17: "A team a day keeps doping away ..."
...

(Thanks to Sergej for updating the scripts) 

Giving a clear separation between presentation graphics and graphics for data exploration is not always easy, because many aspects of the graphics are shared by both types. I very much liked the distinction Antony Unwin gave during one of his latest talks.

Pie charts are as popular as entertaining. The latest highlight of chartjunk is here:

Although the topic "User Interfaces" appears in the title of the blog, I didn't post anything related yet.

Moving into a new office building confronted everybody with the new switches in the offices which control light, temperatures ...

Here is what they look like:

(Sorry for the fuzzy photo, but the 2MP cam in my SE-phone isn't capable of more ...)

The only thing that works as expected here are the light switches, which toggle between ON and OFF - except that you always have to read the text in order to find the desired kind of illumination.

Touching the buttons of the shades makes them go up or down as expected, but the problem arises when you try to stop them. Hitting the button again does not do the job, hitting the button for the other direction reverses the direction but does not stop them either - hmmm?!
The solution: Pressing the buttons for more than 1 second will stop them when you release the button. Unfortunately the delay of 1 second is about the average time people will press the button, resulting in an apparently random behaviour.
The porthole-like windows open and close when pressing the corresponding button - this time they only move as long as you actually press the button.

The highlight is the temperature control. You can press 'cooler' or 'warmer' and ... wait. One very important issue in user interface design is feedback. I actually could not figure out how the temperature control works until I read the manual!
The feedback works as follows:
There will be a red light next to 'cooler' when it is the standard temperature of 21C. When you press 'warner' once it will be 1 degree warmer indicated by a red light next to 'Window open', and once again, i.e., 2 degrees warmer light the LED next to 'Shades up' (as in the picture).
The whole thing works for cooler as well, but now the LEDs will flash to indicate that it is cooler than standard ... The only purpose of the green LED is to indicate that the AC is actually working, which won't be the case as soon as you open the window.
Would you have guessed?

So much for intuitive controls ...