3 Disruptive Mobility in Pre- and Post-COVID Times …
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TAT = WT + AWT
(3.2)
• Next, weights are assigned to each route for each of the PoI with a weight of 1
for the route of highest frequency and 0.5 for all the others.
• Next, Equivalent Doorstep Frequency (EDF) is calculated to treat access time as a
notional average waiting time as though the route was available at the ‘doorstep’
of the selected PoI.
EDF = {0.5 ∗ (60/TAT)} = 30/TAT
(3.3)
• Accessibility Index is calculated for each PoI, differently for the different modes,
using the formula
AI m = EDF max + (0.5 ∗ Sum of EDF of all other routes)
(3.4)
AI POI = Sum of all AI m
(3.5)
• After calculating AI for each of the POIs, they were grouped into nine levels as
explained below and mapped accordingly (Table 3.2).
Table 3.2 Representation of
accessibility index on PTAL
map
PTAL
Access index range Map color
0 (worst) 0
1a
0.01–2.5
1b
2.51–5.0
2
5.01–10.0
3
10.01–15.0
4
15.01–20.0
5
20.01–25.0
6a
25.01–40.0
6b (best) 40.01+
Source TfL [36]