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15_the_circle: (GITS laughing man)
Monday, October 3rd, 2011 08:00 pm

[OT from cottage renovations]
[Crossposted from G+]

Highly effective visualization compresses high volume data - in this case, 55 years worth of Fortune 500 company stats. 

Source: Fathom Information Design via Visual News

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15_the_circle: (capital bikeshare)
Monday, July 11th, 2011 12:50 am

[OT from cottage renovations]

More bikeshare system performance metrics: station availability for several systems in the US and Canada:

Having tracked Capital Bikeshare station availability for a while, it seemed an obvious next step to see how we are doing compared to other systems, at least those for which system status information is readily available. 

Bikeshare Station Availability by City
previous 7 days


  • Our availability, though showing room for improvement, compares favourably to the other systems. 
  • Of the five cities shown above, only ours operates year 'round.  The others are too far north to offer anything other than seasonal service. 
  • Toronto's system is relatively new, having launched a little over a month ago. 
  • Boston will be launching within the next few weeks; their data will be included as soon as it becomes available. 

A side effect of checking availability for these systems is that their respective details (current and previous day bike/dock depletion and station availability maps) are now also available. 

[Edit: added London and Melbourne]

15_the_circle: (capital bikeshare)
Sunday, April 24th, 2011 02:01 am

[OT from cottage renovations]

Rumour has it that Capital Bikeshare will soon be releasing systemwide usage data.  For those of us who derive amusement from such things the data will be interesting to play with analyze and may even yield useful insights. 

This could be quite timely as system usage is on the rise and demand is occasionally approaching or exceeding capacity, fueling much discussion among users and interested observers.  An assertion has been made that one cause of the distribution imbalance is a tendency of users to ride the bikes downhill and then choose some other mode for their return journey, leaving the bikes behind. 

A few days ago over on Housing Complex, Lydia DePillis released a preview containing station usage counts through 9 April.  Even in the absence of trip origin/destination and date/time detail, the usage totals can be used for a simple test of the "lazy user" assertion in the aggregate.  For each station: 

  • compare trips in and out and determine net flow of movements in or out as percentage of total trips;
  • determine elevation by feeding latitude/longitude to the SRTM elevation model via EarthTools web services.



The resulting chart is pretty straightforward, showing clearly that stations at higher elevations tend to be net exporters of bikes and the lower ones tend to be net importers. 

It goes to show that the bikeshare system is just like a railroad: it's necessary to haul those empties back up the hill for the next load. 

15_the_circle: (capital bikeshare)
Sunday, April 24th, 2011 12:46 am

[OT from cottage renovations]

Spring is sprung and as the weather improves Capital Bikeshare usage is experiencing a large but predictable seasonal upswing, augmented by a recent fire sale promotion which doubled membership. 
There are now over 10,000 subscribers. 

The bikeshare system is completely addictive and over the winter was easy to use but it is now becoming increasingly difficult to find a bike or dock when needed and the system operator is having to scramble to keep up with demand. 

It all happens on the margin: each station without a bike is a trip that can’t start (or without an open dock is one that can’t end) representing a service failure for the next subscriber who comes along. 

Since system status is available as a near real time XML feed it didn't take much effort at all to put together a simple page showing bike and dock depletion updated hourly throughout the current day, as well as another one for the previous day’s performance.  If nothing else perhaps they can help subscribers and other stakeholders assess how the operator deals with the situation. 

15_the_circle: (capital bikeshare)
Saturday, March 12th, 2011 12:08 pm

[OT from cottage renovations]

There's nothing more frustrating than having an elegant solution for which no problem can be found and for some time now -- many months actually -- I've been trying to find an excuse to play with use the Circos visualization tool.  I had anticipated that its best potential would lie in finding patterns in some reasonably sparse matrix and traffic flows on a network (whether information or physical) seemed like the best bet. 

For the past couple of months now I've been an enthusiastic user of (which is to say: hopelessly addicted to) the Capital Bikeshare system.  CaBi has restored an exercise component to my quotidian routine and facilitated a modal shift in my daily commute away from the increasingly unpleasant Metro system.  Systemwide bikeshare usage information has not yet been released but individual subscribers have access to their own usage history, from which one can see their own contribution to the whole.  So far it looks like this

[click on image below for details]

With over 5,000 subscribers, any individual slice through data is going to represent a sample of under 0.02%.  This figure and the page on which it appears are updated daily but things won't really get interesting until they get around to releasing a larger data set.