SCGE (S̄patial C̄omputable Ḡeneral Ēquilibrium) model has been developed as a comprehensive policy assessment methodology in the infrastructure planning and management field. Since this field is strongly interested in spatial economic impacts of transport policy, disaster shock and so on, many researches have made efforts to improve how to model the “spatial” interaction via transport system. This article reviews the development of SCGE models in the infrastructure planning and management field as an introduction of the special issue “Frontier of spatial computable general equilibrium analysis in the infrastructure planning and management” and describe the breakthrough of each paper included in this issue. We furthermore mention some perspectives of the future research.
Computable general equilibrium (CGE) model is widely used to investigate the economic impacts of freight transportation cost reduction brought by the development of transportation infrastructure. When using CGE model for this kind of policy evaluation, it is important to model the freight transportation cost appropriately with the limited availability of data. This study considers two representative models of transportation cost. The first is 1) iceberg transportation cost model and the second is 2) transportation sector model. With both analytical calculation and numerical simulation, this study identifies the properties of the bias of each model’s assumption that distorts the evaluation of the economic impacts of transportation cost reduction. Then, this study considers the appropriate modeling of transportation cost and the appropriate procedure when using CGE model in order to reduce these bias.
Iceberg transport cost model is widely employed to describe transportation cost in theoretical economic analysis and quantitative analysis such as Spatial Computable General Equilibrium (SCGE) analysis. Iceberg transport cost is, however, assumes that the production of goods and the transportation of the goods are conducted using same production technology. Therefore, in SCGE model, each production sector produces goods and the transportation services of the goods. The problem of SCGE model with iceberg transport cost model is that the level of goods production and their transportation are indistinguishable. This study analyzes the problem theoretically and quantitatively. The quantitative analysis is conducted using two types SCGE models: a SCGE model employing iceberg transportation cost model and employing non-iceberg transportation cost model. The quantitative analysis shows that a SCGE model employing iceberg transportation cost model is not suitable to assess the change in the level of goods production caused by traffic improvement.
A recent study by Akamatsu et al.1) has provided a simple classification of economic geography models according to their comparative static properties with respect to transport costs in a homogeneous geographical space. This study clarifies that models belonging to diﬀerent classes have qualitatively diﬀerent behavior even when evaluating the impact of transport infrastructure improvement in a heterogeneous geographical space. Specifically, by comparing a pair of new economic geography models, Helpman13) and Pflüger and Tabuchi17), we demonstrate that an improvement in transport access disperses population from larger regions in the former model, while it enlarges the population size of larger ones in the latter.
The purpose of this paper is to examine measures for maximizing the stock effect of road network based on the economic effect measured by SCGE model. To begin with, the stock effect of the road network improved in the past is measured using the SCGE model as a potential. Then, this potential was compared with the measured value of the economic change based on the Industrial Production Index, and the existence of the actualization of the stock effect was analyzed. Finally, this paper clarifies factors in which effects have appeared or not appeared by enterprise field study, and shows barriers and countermeasures for maximizing stock effects of road network.
Congestion in the morning commute at several urban railways and stations is a serious problem in Tokyo metropolitan area. Discussing the required capacity upgrades to accommodate current travel demand is an important process in promoting of capacity investments. Under ideal conditions moving block signaling system (MBS) can provide headways of 90 seconds or less without construction works for the quadruple track. Passengers would see substantially less waiting and crowding with MBS that equates to 40 or more trains per hour.
In this paper, the authors have studied possibilities of high frequency train operation using MBS for the Denen-toshi line and Hanzomon line in Tokyo Metropolitan area as a case study. Two methods were used for that purpose. More speciﬁcally, a theoretical approach for train operation and an agent-based simulation approach were conducted. It was found that the case study line with improving both the Shibuya station capacity and communication delay is probable to operate at headways of 95 seconds.
Mashiki town conducted questionnaire surveys following the 2016 Kumamoto earthquake. The survey aimed to capture the disaster victims’ residential preference and predict the demand for disaster public housing. To achieve a high response rate, reminders were sent in a mail-based survey, and additional interview surveys were administered to non-respondents from the mail-based survey. This study aims to examine (1) the effects of these additional efforts in mixed surveys by revealing the household sample differences in various examples of response timing, and (2) the nonresponse bias in estimated public disaster housing demand. We found that households with younger heads-of-households, households with children living in temporary housing, and households in post-disaster public-funded rental housing considering housing relocation tend to delay their response or to be non-respondent for mail-based surveys. Our findings indicate that demand might be overestimated with simple prediction methods. Specifically, the demand by temporary housing tenants was overestimated more than that by post-disaster public-funded rental housing tenants.
In this study, a methodology is proposed to analyze stationary distributions of urban/transportation equilibrium models which would have multiple equilibria due to economies of scale, clearly considering dynamic uncertainty of systems of the models. First, in a framework of continuous time and continuous states, it is clarified that the stationary distribution has a Boltzmann type analytical solution when the urban/transportation equilibrium model can be classified into the potential game and the dynamics of the system follows a specific stochastic process. Second, a method is developed to estimate the stationary distributions with a Markov chain Monte Carlo method. Lastly, the proposed methodology is demonstrated by applying it to a problem to estimate stationary distributions of a spatial agglomeration model, and it is found that the stationary distributions can be estimated with the proposed methodology even if the model has large agents and its stationary distribution cannot be estimated with the existing methodologies.
The water transportation projects of Tokyo waterfront area are expected to be promoted in preparation for the 2020 Tokyo Olympics. The water transportation should be promoted as a tourism business because it provides extraordinary scenery to the passengers. However, there are very few cases of water transportation projects that have continued for more than 10 years, so that business ideal way is needed. Therefore, this study clarified the transition of the route and the business method through the pamphlet analysis and interview survey of the water transportation brochures in Tokyo waterfront. As a result, this study grasped the following three features.
1st term (1971-1995): Establishment of the business route by lunch and dinner cruise type and landscape experience type. 2nd term (1996-2011): Establishment of the round-trip route based on historical and cultural experiences in small rivers of Tokyo. 3rd term(2012-present): Establishment of free route setting type.
Recently, various kinds of car sharing and ride sharing service have become popular in the world. At the same time, the number of users of P2P car sharing services that does not need dedicated parking lot and vehicle is increasing also. Moreover, a new mobility service supplying this service with an autonomous driving vehicle has attracted attention. This research investigates the introduction possibility and effect of Autonomous Vehicle Sharing Services which is combined P2P car sharing and autonomous driving vehicle by a simulation model including both traveler’s modal choice and supplier’s lending behavioral models.
We examine the causal effects of the toll reform scheme that started in April 2016 for the Metropolitan Tokyo on traffic demand. Firstly the spatial panel data regression has been performed for the OD traffic demand obtained from the electronic toll collection data and we ﬁnd a signiﬁcant causality of tolling on traffic demand. Second, we have applied an aggregate route choice mode that accommodates panel effects and ﬁnd the signiﬁcant route shift from the Metropolitan Expressway to the Inter-City Expressway. Finally, we have estimated the net causal effects of the toll reform scheme and ﬁnd that indeed the route traffic shift has been conﬁrmed though it has little effects on the total traffic demand.
In this paper, the analytical solution of transition probabilities between condition states in the hierarchical hidden Markov deterioration model is derived. The analytical solution enables us to i) improve accuracy of parameter estimates, and ii) reduce computational time to estimate parameters. i) and ii) are investigated in numerical examples comparing estimated parameter sets using an existing method and the proposed method with the analytical solution.