The Cross-assessment Approach: A Tool for Vision-led Planning
As discussed above, there is a trade-off between promotion of urban activity and GHG emission reductions. The balancing point between them may depend on the evaluation standard. The standard may differ even by person, depending on his/her position or ideology. People may make a judgement based solely on their own standard without referencing other standards. To better integrate strategies, a wide range of stakeholders with different values should be encouraged to fully participate in strategy formulation. This enables the development of a common understanding of policy objectives and a shared vision for the sustainable city. To make it possible, we need to reconcile conflicting objectives among stakeholders by clarifying the pros and cons of respective strategies and meet the requirements of a sustainable society.
As a tool for supporting the shared vision formation, we have developed a strategic cross-assessment model (Doi and Kii 2012). The cross-assessment combines the essential elements of multi-criteria analysis and conflict analysis (Keeney and Raiffa 1993; Toman 1994; Knoflacher and Himanen 1991; Dodgson et al. 2000; Minken 2002). It aims to explore synergistic solutions combining different value systems by assessing the impact on all outcome factors of measures pursuing each value factor, as shown in Fig. 3. An iterative feedback in the figure indicates that an appropriate weighting and combination of three value factors should be examined based on the results of the cross-assessment. Decisions are usually made based on consensus among stakeholders whose value systems are different from each other. Each of the three strategies in this study is based on a particular value factor, and is evaluated for the impacts on all of the outcomes.
We set the triple bottom lines of sustainability as economy, society, and environment, assuming the following three strategic targets in transport policy: (1) Profit maximisation of the public transport operator; (2) Net benefit maximisation; and (3) CO2 emissions minimisation in the transport sector. The first target is equal to minimisation of subsidy by the government. In the second, net benefits are defined as the sum of user benefits and operator profits. Based on these targets, we set three outcome indices; operator profits, user benefits, and CO2 emissions. The outcomes of these three strategies are shown in Fig. 4.
Fig. 3 Concept of cross-assessment in this study Source prepared by authors based on Doi and Kii (2012)
Fig. 4 Comparison of estimated outcomes of strategies Source prepared by authors based on Doi and Kii (2012)
Comparing with the “business as usual” (BAU) case in 2030, the profit maximisation strategy is estimated to largely decrease the public transport operation deficit and CO2 emissions as well; however, the user’s benefit will be largely negative because of the decline of level of service of public transport This strategy will decrease the services offered by unprofitable operators. That contributes to a reduction in CO2 emissions because unprofitable operators cease bus and train services where there is little ridership.
The CO2 emission minimisation strategy largely reduces the emissions, and also results in an improved financial balance of the public transport operation. In addition, the user’s benefit is slightly positive. Different from the profit maximisation strategy, some public transport operators may increase their service level to shift the demand from car to public transport, which reduces CO2 emissions. Of course, some operators cease service at lower demand routes, but in an aggregated figure, the user’s benefit is slightly positive.
The net benefit maximisation strategy largely increases the user’s benefit, but the financial balance of the public transport cannot be improved, and furthermore, CO2 emissions slightly increase. This indicates that prioritising the user’s convenience justifies inefficient operation, allowing its service to continue. When evaluating these three strategies, the CO2 minimisation strategy has the most balanced effect on the three outcome indices.
The cross-assessment framework evaluates optimal strategies based on various value standards using the outcome indices corresponding to the value standards. This method makes it possible to comprehend the synergy and trade-off among the strategies, and it can contribute to building a shared vision and consensus among stakeholders with different value standards, resulting in balanced policy formation.