Figure 3

Bootstrap for weekdays. (a) shows the results of the bootstrap for couples of Large cities during the weekdays. The point and the bars represent the mean and the variance obtained for each couple through the jackknife sampling method. The shaded area represents the 95% confidence interval obtained using the bootstrap method described in Materials and methods and the line represents the bootstrapped Weighted Least-Square Regression (WLS) fit. (b) as (a) but for the Medium cities. (c) as (a) but for Small cities. (d) summarizes the estimates of the bootstrap regression previously obtained in figures (a)–(c). Note that 95% confidence intervals for all the classes mostly do not overlap. Detailed statistics are reported in Table 1