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Table 5. Results for an unmarked crosswalk model. Parameter Estimate S.E.* 95% Confidence Limits p-Value Intercept −12.11 2.59 (−17.18, −7.04) < .0001 Log (ADP) .64 .13 (.37, .90) < .0001 Log (ADT) .55 .26 (.04, 1.05) .0319 Median −1.27 .45 (−2.14, −.39) .0047 Eastern region −1.31 .48 (−2.25, −.38) .0060 Dispersion 1.18 1.30 (.14, 10.23) – *S.E. = Standard Error Table 6 shows the estimates of these model parameters were again consistent across the eight data subsets. The estimates marked with an asterisk (which were not significant at a .05 level) were the ADT effect on the subset with Seattle, WA, data omitted, and the ADT effect and eastern region effects on the subset with New Orleans, LA, data omitted. The p-values for these estimates were .06 in each case. Table 6. Parameter estimates for unmarked subset models. Estimates on Subsets Parameters Seattle San Francisco Oakland New Orleans Milwaukee Cleveland Gainesville Cambridge Intercept −11.19 −12.43 −11.89 −11.80 −11.92 −12.72 −11.94 −12.48 Log (ADP) .56 .69 .64 .52 .64 .69 .66 .65 Log (ADT) .48* .54 .52 .54*.52 .58 .52 .58 Median −1.24 −1.17 −1.17 −1.07 −1.25 −1.16 −1.24 −1.30 Eastern region −1.28 −1.23 −1.25 −.93*−1.56 −1.29 −1.03 1.03 * Not statistically significant at .05 level. While the models presented above examine the effects of medians, crosswalk designs, and other factors on pedestrian crashes, the primary factors associated with these crashes were shown to be pedestrian volumes and traffic volumes. Analyses based on the data shown in table 1 indicated no significant difference in the safety of marked and unmarked crosswalks on streets having two or fewer lanes, while marked crosswalks were less safe overall on multilane roads. The models suggest a further examination of multilane roads as a function of varying traffic volumes and the presence of raised medians. Table 7 shows pedestrian volumes, crashes, and average exposure years for a number of categories defined by number of lanes, traffic volumes, and median type. Using the same approach as for table 1, a marked crosswalk exposure proportion, pmi, was computed for category i, as 22 (5) where (6) where the sum extends over all sites (S) in category i, Xmi is the total exposure for marked crosswalks in category i, and Xumi is similarly defined as the total exposure for unmarked crosswalks in category i.