Relation between the trip duration and the distance traveled by bike users in Chicago and New York.

In (a) and (b), we present hexagonally binned two-dimensional histograms for the logarithm of τ/τ0 and the logarithm of the corresponding quantity d/d0 where τ0 = 1s and d0 = 1Km are reference values. The colors codified in the colorbar represent the number of travels f(τ, d) found in each hexagonal bin. For the results in both cities, the dashed lines depict the relation d = v⋆τ where v⋆ is an effective speed (v⋆ = 10 Km/h for Chicago and v⋆ = 9 Km/h in New York). This relation is explored in (c) where we analyze the values of the average speed for each of the trips. We obtain the probability density p(v) by using linear bin counts with size Δv = 0.05 Km/h. Our findings reveal marked peaks for the values of the speed that appear with high probability in each city and coincide with the value v⋆ reported in (a) and (b).