The preliminary spatiotemporal study is conducted in the Taipei metropolitan area, the largest metropolis in Taiwan, in which population is estimated at 6.63 million inhabitants and the total area is 2,265 km2 in 2005. Besides, the number of registered private vehicle is 4.67 million involving 1.51 million cars and 3.16 million motorcycles. The length of roads is estimated at 4,007 kilometers with the exception of roads whose width is lower than 6 meters.
In order to explore the difference of transport diversity in the spatial aspects, the Taipei metropolitan area was divided into five sub-zones, such as urban core, urban area, satellite towns, suburban area, and rural area, according to socio-economic characteristics. GIS was utilized to overlay pictures with data layers. For instance, the MRT accessibility is overlaid with resident population and service area of feeder buses as shown in Figure 4-1.
FIGURE 4-1 MRT accessibility layers
According to Section 3.2, this section chooses 12 indicators based on the conceptual framework as shown in Figure 2-1 to demonstrate the feasibility and usefulness of transport diversity analysis. The present values of indicators are gained from the statistics and metadata.
In addition, the goal values of indicators are generated by the Taipei’s White Paper to identify the targets towards sustainability from the government perspectives in planning process. An expert interview program is adopted for understanding each appropriate level with which stakeholder satisfies the basic needs to live without deficiencies. Both the goals and thresholds are employed for normalizing the gap of each stakeholder need between the goal and present values.
The results of transport diversity analysis consist of temporal and spatial aspects. In the temporal aspect, a representative set of indicators and transport diversity in 2000 are shown in Table 4-1. The achievements within the indicators are extremely low except MRT accessibility.
In fact, safety, emission, bus reliability and level of universal design are the lowest because the present value has not reached the threshold. Affected by the shortage of needs’ groups, the value of transport diversity is relatively lower to 2.15.
TABLE 4-1 Performance on transport diversity in 2000
Indicator Present
Value Goal Value Threshold
Value
m
in
i =∑
i i i
i n
P n
Emission 46.93 25.00 45.00 1.10 0 0
Safety 1.13 0.20 1.00 1.16 0 0
MRT Accessibility 0.78 0.85 0.60 0.28 0.72 0.17
Bus Accessibility 0.61 0.85 0.60 0.96 0.04 0.01
Road Connectivity 0.27 0.50 0.25 0.92 0.08 0.02
Pedestrian Accessibility 1.31 2.00 0.80 0.58 0.43 0.10
Auto Mobility 26.50 35.00 20.00 0.57 0.43 0.10
Bus Mobility 0.63 0.80 0.40 0.43 0.58 0.13
Bus Reliability 0.61 0.85 0.65 1.20 0 0
MRT Affordability 0.10 0.07 0.15 0.38 0.63 0.15
Bus Affordability 0.06 0.04 0.10 0.33 0.67 0.16
Resource Over-Utilization 229.25 150.00 250.00 0.79 0.21 0.05
MRT Operator Profit 144.56 20.00 150.00 0.96 0.04 0.01
Bus Operator Profit 72.60 120.00 30.00 0.53 0.47 0.11
Level of Universal Design 0.35 0.70 0.50 1.75 0 0
∑
mi = 11.92 H=−∑
PilnPi =2.15Table 4-2 shows the performance on transport diversity in 2005. The summation of normalized gap has been decreased from 11.92 to 8.57 due to the significant reductions in the accident rate and the contaminated air, as well as the improvement of bus reliability. Moreover, the transport diversity value has been increased to 2.51. The analytical results reveal that the stakeholder needs in 2005 had been satisfied more equitably than that in 2000. However, the modification of level of universal design has not achieved the expectation of stakeholders,
along with deficient satisfactions of air pollution, bus accessibility and road connectivity.
TABLE 4-2 Performance on transport diversity in 2005
Indicator Present
Value Goal Value Threshold
Value
m
in
i =∑
i i i
i n
P n
Emission 43.39 25.00 45.00 0.92 0.08 0.01
Safety 0.53 0.20 1.00 0.41 0.59 0.09
MRT Accessibility 0.76 0.85 0.60 0.36 0.64 0.10
Bus Accessibility 0.65 0.85 0.60 0.80 0.20 0.03
Road Connectivity 0.29 0.50 0.25 0.84 0.16 0.02
Pedestrian Accessibility 1.47 2.00 0.80 0.44 0.56 0.08
Auto Mobility 27.70 35.00 20.00 0.49 0.51 0.08
Bus Mobility 0.68 0.80 0.40 0.30 0.70 0.10
Bus Reliability 0.73 0.85 0.65 0.60 0.40 0.06
MRT Affordability 0.09 0.07 0.15 0.25 0.75 0.11
Bus Affordability 0.06 0.04 0.10 0.33 0.67 0.10
Resource Over-Utilization 203.18 150.00 250.00 0.53 0.47 0.07
MRT Operator Profit 52.67 20.00 150.00 0.25 0.75 0.11
Bus Operator Profit 48.32 120.00 30.00 0.80 0.20 0.03
Level of Universal Design 0.45 0.70 0.50 1.25 0 0
∑
mi = 8.57 H=−∑
PilnPi =2.51In the spatial aspect, the transport diversity of sub-zones would be explored with the exception of rural area because the transport infrastructures and services in rural area have been insufficient for the basic needs of most stakeholders and the limited data availability.
Furthermore, some indicators including reliability, affordability, operator profit, resource consumption and level of universal design excluded from the spatial analysis due to the unavailable zonal data. Figure 4-2 indicates that safety could be improved considerably. In particular, the present values of safety are 0 in both satellite towns and suburban area.
Additionally, the achievements of emission for all sub-zones have not exceeded 35%. On the contrary, the achievements of MRT accessibility and bus accessibility in urban core have reached the goal. The performances of auto mobility and MRT accessibility in urban area are relatively higher. Furthermore, the higher needs satisfaction in satellite towns and suburban area are bus accessibility and auto mobility, respectively.
FIGURE 4-2 Achievement of indicators in spatial patterns
The additional information of spatial analysis could be determined from Table 4-3. The sub-zone namely satellite towns, having the most numerous indicators failing to stand on the thresholds, shows the lowest diversity. By comparison, urban core with the stakeholder needs that are satisfied more equitably has the greatest value of transport diversity and the smallest gap. Further analysis of Table 4-3 would appear to suggest that the higher diversity sub-zones have a trend to be smaller in gap. In fact, the outcomes of the analysis would help transport planners to understand what infrastructures or services at where have to be improved. For example, the speed limit, road shape, and directional divided facility have to be reassessed in the satellite towns and suburban area to reduce the accident rate. Therefore, none of the stakeholder needs could be neglected.
TABLE 4-3 Transport diversity in spatial patterns
Indicator Urban Core Urban Area Satellite Towns Suburban Area
Level of Bus Service 0.12 0.10 0.09 0.07
Auto Mobility 0.12 0.20 0.12 0.32
Safety 0.13 0.03 0 0
MRT Accessibility 0.18 0.20 0.14 0.07
Bus Accessibility 0.18 0.15 0.26 0.11
Level of Pavement Service 0.11 0.11 0.20 0.19
Road Connectivity 0.11 0.14 0.19 0.19
Pi
Air Pollution 0.05 0.07 0 0.05
Summation of Normalized Gaps: 2.42 3.30 4.84 5.80
Transport Diversity 2.03 1.97 1.73 1.76