Figure 2

Values of α and β for the 24 cities studied. The boxes represent 95% confidence intervals obtained with a bootstrap, for empirical best-fits for the model parameters. The differences we observe in the accessibility time α and in TTB β are thus significant and uncorrelated (\(r = 0.09\)). Both timescales are weakly correlated with the city’s population (\(r = 0.20\) for α and \(r = 0.40\) for β).