New paper on trip and station level data formalization, trip count estimation

[Cyrille Médard de Chardon]

Hi,

Here's our new paper that formalizes the relationship between station level and trip data. This allows a rough estimate of rebalancing amounts among other benefits. We also created some models to estimate number of trips based on changes to station state data over time.

Paper:
http://www.sciencedirect.com/science/article/pii/S0191261515000983

I also slogged through making audio slides if that's of interest: http://audioslides.elsevier.com/ViewerSmall.aspx?doi=10.1016/j.trb.2015.05.003

Highlights:

- We formalized the relationship between bicycle-sharing trips and station level data.

- Our methodology extracts station specific temporal rebalancing quantities.

- We define three aggregate models to estimate temporal and station activity.

- Publicly available station level data can effectively estimate BSS daily trip counts.

Abstract:
Bicycle sharing systems (BSS) have increased in number rapidly since 2007. The potential benefits of BSS, mainly sustainability, health and equity, have encouraged their adoption through support and promotion by mayors in Europe and North America alike. In most cases municipal governments desire their BSS to be successful and, with few exceptions, state them as being so. New technological improvements have dramatically simplified the use and enforcement of bicycle return, resulting in the widespread adoption of BSS. Unfortunately little evaluation of the effectiveness of differently distributed and managed BSS has taken place. Comparing BSS systems quantitatively is challenging due to the limited data made available. The metrics of success presented by municipalities are often too general or incomparable to others making relative evaluations of BSS success arduous. This paper presents multiple methodologies allowing the estimation of the number of daily trips, the most significant measure of BSS usage, based on data that is commonly available, the number of bicycles available at a station over time. Results provide model coefficients as well as trip count estimates for select cities. Of four spatial and temporal aggregate models the day level aggregation is found to be most effective for estimation. In addition to trip estimation this work provides a rigorous formalization of station level data and the ability to distinguish spatio-temporal rebalancing quantities as well as new characteristics of BSS station use.

Cheers,
Cyrille