tungwaiyip.info

home

about me

links

Blog

< February 2014 >
SuMoTuWeThFrSa
       1
2 3 4 5 6 7 8
9101112131415
16171819202122
232425262728 

past articles »

Click for San Francisco, California Forecast

San Francisco, USA

 

Make Useful Charts

Having been with Bay Area Bike Share for a few month, I am glad with their green bikes available around downtown. I also appreciate Bay Area Bike Share's openness in sharing their system metrics. However the system chart on their web page do not provide much useful information.

Official Chart

The slowly raise bar chart shows cumulative trips taken since launch. The chart may look boring, but as least the upward trend looks comforting, right? Wrong! A cumulative chart by construction can only go up. The comfort feeling is misleading. A more useful way is to chart the number of trips taken by week. Also, data from 5 cities are available individually. So why not plot them side by side for comparison. I did a little work to make an improved chart below.

Improved Chart

Some information immediate obvious from the chart is that nearly all trips were made in San Francisco, despite it only has half of the resources deployed. Clearly the bike share program is not working out in the Peninsula at all given their negligible usage. Secondly, there are ups and downs in usage that cannot be observed from the upward looking bar chart. After the first few months the usage has peaked at about 6,000 to 7,000 trips per week, then fallen sharply in December due to holidays. The January number has yet to recover to reach the usage last year.

This is not mean to be critical. It is just to demonstrate how an useful chart can inform us.

This is the link to the simple source code by Pandas.

2014.02.24 [] - comments

 

 

blog comments powered by Disqus

past articles »

 

BBC News

 

Prague gunman killed himself on roof as police approached (22 Dec 2023)

 

Bodycam footage shows police hunting Prague gunman (22 Dec 2023)

 

Alex Batty: Police launch abduction investigation into disappearance of British teen (22 Dec 2023)

 

Banksy stop sign drones art removed in London (22 Dec 2023)

 

Martin Kemp refunds disabled ticket after fans' difficulty with seller (22 Dec 2023)

 

Queues at Dover as Christmas getaway begins for millions (22 Dec 2023)

 

New £38,700 visa rule will be introduced in early 2025, says Rishi Sunak (22 Dec 2023)

 

UK at risk of recession after economy shrinks (22 Dec 2023)

 

Mohamed Al Bared: Student jailed for life for building IS drone (22 Dec 2023)

 

Andrew Tate denied request to visit ill mother in UK (22 Dec 2023)

more »

 

SF Gate

more »


Site feed Updated: 2023-Dec-22 09:00