Has the Citibike expansion in May changed the usage of popular Citibike stations and popular routes in NYC?
To continue from our last article, Citi Bike announced its expansion plan and installed more than 100 new stations across northern Manhattan and the South Bronx starting the week of May 4th, 2020. This was to become a more equitable transportation system, and COVID-19 pandemic has given the expansion renewed urgency.
Now, it has been half a year after the expansion, and how are New Yorkers doing with the new Citi Bike stations? Here is a new question — Has the Citibike expansion in May changed the usage of popular Citibike stations and popular routes in NYC? By looking into the Origin-Destination analysis of Citibike rides data, let’s see if there are any interesting changes.
Data used for the analysis: Citi Bike trip history data of April and September 2020. (https://www.citibikenyc.com/system-data)
Yellow dots in the directed graphs represent the Citibike stations across New York City. Black lines connecting them are the Citibike rides in April(left) and in September(right) 2020. By looking at the graphs, we can easily notice that newly installed stations were heavily used as much as the other stations by Newyorkers after the expansion. Not only that, the total number of Citibike rides per month rose. In April, the total number of rides was 682,762, while in September, it was 2,488,225 — meaning that number of rides per month got 3 times bigger in just in 5 months.
Let’s take a closer look at the Citibike rides in April 2020. As you can see in the chart, Stations with the biggest number of incoming rides usually have the biggest number of outgoing rides as well. Only 2 stations are different among 10 stations.
By zooming into the geographic locations with the most incoming rides and outgoing rides, there seemed to be two keywords in these locations — Accessibility, and Hospital.
Accessibility: 5 stations were located right next to the bridge or ferry terminal that connects Manhattan to other boroughs(S 5 Pl & S 5 St station, S 4 st & Wythe ave station, Kent Ave & N 7 St station, 1 ave & E 62 st station, 12 Ave & W 40 St station). Moreover, 6 stations were located near subway stations or popular destinations such as Central Park, Union Square Market, midtown(E 17 St & Broadway station, Central Park & 6 Ave station, Grand army plaza & Central park station, Broadway & W 25 st station, West st & Chambers st station).
Hospital: 2 stations were located right next to the hospital (E 33 St & 1 Ave station, 1 Ave & E 68 St station). Since COVID-19 crisis, Mayor de Blasio announced free Citibike memberships for critical workforce in response to COVID-19. We can assume that the high number of routes of these 2 stations were due to the increasing number of critical workers using citibike for their commute.
By looking at the maps above, we can compare the top 10 Citibike stations that have the most number of outgoing and incoming rides in each month. Maps show that half of the top 10 stations in April matches with that of September. From this result, we can partially answer the question — Has the Citibike expansion in May changed the usage of popular Citibike stations and popular routes in NYC? We can answer that there was a change in the popular stations after the expansion.
In Degree Centrality, the more connections the node has, the more important it is. This means that S 5 Pl & S 5 St Station was the most important and concentrated Citibike station in New York City in April but 1 Ave & E 68 St Station was the one in September. Moreover, closeness centrality means the closeness of a central node to other nodes. We can assume that 5 Pl & S 5 St Station was the closest note to all the other nodes in April but 1 Ave & E 68 St Station was the one in September.
Also, by looking at the graph, we can notice that the degree centrality of Citibike stations got bigger. This is specifically shown in the chart above since the degree centrality of the top 1 station in April (S 5 Pl & S 5 St Station) was 1015 while the degree centrality of the top 1 station in September (1 Ave & E 68 St Station) was 1335. Also, all of the top 10 stations of September had the bigger degree centrality than all of the top 10 stations of April.
Furthermore, by looking at the 3 Citibike routes that were most popular in April and September, we can see a notable difference after the expansion — 2 among 3 routes were changed. What’s interesting is that all 3 routes’ start station and end station are identical. This means that the user finished his/her ride where he/she started.
Surprisingly, 3 Stations were located right next to the park. From these pieces of evidence, we can assume that these rides are for exercise or leisure rather than for commute.
One more interesting point was that the Citibike station located in Governer’s island(Soissons Landing Station) was ranked as the second most popular route in September. This is interesting not only because Governer’s island is isolated from Manhattan, which has most of the Citibike stations, but also because this station was newly installed by the expansion in May. Which means that there was no single Citibike ride in the island in April, but after 5 months, it has become one of the most loved biking routes of Newyorkers. Since the route’s start station and end station are identical, we can assume that Citibike-riders enjoy traveling around this island, and dock their bike at the station they started. This clearly shows that the Citibike expansion was meaningful and especially relevant in today’s time in a sense that it enhanced the accessibility to the green space of Newyorkers.
