This paper derives incentives for voluntary interregional coordination and the conditions for coordination agreements using a model of non-cooperative provision of regional public goods targeting multiple regions.　The interregional coordination discussed here is limited to two areas.　The first is a policy to coordinate the relaxation of restrictions on access to regional public goods by residents of other regions.　The second is to relax access to public goods in one region for residents of other regions and, in return, receive transfers from other regions.　Under such circumstances, the incentive for regions to coordinate with each other is that regional coordination will improve the welfare of each region beyond its initial state.　This requires that the coordination policy be Pareto-improving.　If this transfer is partial, it corresponds to the partial outsourcing of public goods provision to other regions.　If all public goods are outsourced to other regions and all public funds are transferred in return, this corresponds to a situation of merger （absorption）, in which the region is completely absorbed by other regions.　The former consists of the transfer of financial resources for the provision of joint public goods, while the latter consists of the complete outsourcing of public goods provision.　To analyze these issues, we first present a public goods game for two regions and examine the regional coordination problem.　I then show that the coordinated relaxing of public goods access is Pareto-improving.　Furthermore, we derive the conditions under which regional coordination can be achieved when interregional transfers are available.　Next, I apply the analysis of the two region model to the coordination problem between the central city and several neighboring regions.　This central city-neighboring regions model reflects the actual structure of interregional coordination, and therefore identifies the conditions for agreement on regional coordination.　From the analysis of regional coordination, when the initial state is non-cooperative, it can be shown that 1） if all regions are completely identical, cooperative relaxation of access to public goods improves the welfare of each region;2） if regions are asymmetric, the degree of relaxation of access also differs between regions;and 3） if interregional transfers are available as compensation for unilateral relaxation of access to public goods, such regional coordination is Pareto-improving.

JEL Classification:H41, H72, H73, R52

　　In this paper, we used the D9SCGE model to clarify the impact of two agricultural policies, namely the promotion of the active utilization of smart agricultural technology and the promotion of exports of agricultural, forestry and fishery products and food, on Japan’s food self-sufficiency ratio and regional economy through the expansion of domestic agricultural and food production.　The following points were clarified in this paper.　First, a cost-benefit analysis of the policy goals stipulated in the Act on Promoting the Utilization of Smart Agricultual Technology showed that if smart agricultural technology was used on most cultivated areas by 2035 with the current budget scale and the government’s target of agricultural labor productivity of 5% or more was achieved, the benefits （equivalent variance） did not exceed the total costs （cumulative budget amount）.　In order for the benefits to exceed the total costs, it is necessary to consider a policy framework for raising agricultural labor productivity to 6-7%.　Second, if the productivity of the agricultural sector increased to the same level as the potential growth rate and land intensification was promoted, Japan’s food self-sufficiency rate did not exceed the 2025 level estimated from this model unless two agricultural policies, the spread of smart agricultural technology and export expansion measures, were implemented.　For this reason, if these two agricultural policies were steadily implemented, Japan’s food self-sufficiency rate increased by 2% to 3% from the 2025 level by 2050.　Third, with regard to the impact on the regional economy, if productivity in each industry increased to the level of potential growth, the GRP in the Tohoku region was heavily affected by the population decline, and grew only 0.3% by 2035, and was almost zero by 2050.　On the other hand, it was found that the GRP in the Kanto and Chubu regions grew at a rate higher than the potential growth rate.　Thus, looking at the impact on agricultural production in a situation where the gap in the regional economies between urban and rural areas was expected to widen due to the population decline, it was found that with the spread of smart agricultural technology and measures to expand exports, agricultural production in Tohoku, Kinki, and Shikoku grew 0.1% to 0.3% between 2035 and 2050, and Hokkaido, Kanto, and Kyushu, with a high weighting of agricultural production, was able to secure a growth rate of 0.6% to 0.7%.

JEL Classification:C68, Q16, Q18, R13

　　This study aimed to evaluate the effects of different cover materials on environmental efficiency in controlled environment horticulture, taking into consideration the regional characteristics of Wakayama Prefecture.　First, model facilities and cultivation conditions for controlled environment horticulture were established at multiple cultivation sites within Wakayama Prefecture.　Subsequently, existing cover materials widely used in the field were selected, and comparisons constructed by combining these materials.　Next, tools such as yield estimation, improved fuel estimation, and equipment introduction estimation tools were used to calculate greenhouse gas （GHG） emissions and business revenues.　Finally, environmental efficiency was calculated based on the derived GHG emissions and business revenues.

　　The results showed that Ethylene Tetrafluoroethylene （ETFE） agricultural film had the highest environmental efficiency in all evaluation regions, while Polyolefin （PO） agricultural film had the lowest environmental efficiency.　Furthermore, there were significant differences in environmental efficiency between regions, with the largest variation observed in Pattern 3 （PT3） （outer layer:ethylene tetrafluoroethylene film – inner layer:agricultural vinyl film） and the smallest in Pattern 2 （PT2） （outer layer:agricultural polyolefin film – inner layer:agricultural polyolefin film）.

　　The differences in environmental efficiency between regions were strongly influenced by fluctuations in heating loads due to the use of heating oil, reaffirming that the environmental efficiency of agricultural cover materials are significantly affected by regional climate conditions.　These results confirm that achieving decarbonization and sustainability in facility horticulture requires evaluations tailored to regional conditions.　The combination of cover materials in PT3 demonstrated relatively low greenhouse gas emissions and the potential to increase sales revenue, suggesting the importance of selecting optimal cover materials based on regional climate characteristics.　To improve environmental efficiency in the future, it is necessary to consider not only the selection of cover materials but also the introduction of low-carbon heating technologies such as heat pumps and combinations of carbon dioxide dispersion methods tailored to regional conditions.　A strategic approach that takes regional characteristics into account is essential, rather than a one-size-fits-all approach.　Future challenges include optimizing planting times by region and analyzing the aging degradation of inner cover materials.

JEL Classification:Q51, Q54

　　The purpose of this study was to clarify recent changes in the rice purchasing behavior of Japanese consumers through an analysis of the e-commerce （EC） market, with particular attention on the transformation of market structure and shift in brand perception from an information-based to a meaning-based orientation.　Two hypotheses were established:（1）Japan’s rice EC market functions as a monopolistic competition market characterized by product differentiation;and （2） consumer brand perception is shifting from information-based brand value─derived from objective product attributes─to meaning-based brand value co-created through consumption experience and reviews.

　　To verify these hypotheses, product data were collected from three types of EC platforms─specialized rice stores, direct-from-producer sites and general e-commerce sites─and were analyzed using a hedonic pricing model.　The results showed that attributes such as brand（variety×production area）, certification and small package size have statistically significant effects on prices across all platforms.　These findings support Hypothesis 1 and indicate that the rice EC market indeed functions as a differentiated monopolistic competition market.　Moreover, platform-specific patterns were observed:specialized stores show relatively concentrated price ranges for well-known brands, direct-from-producer sites show wide price dispersion reflecting strong consumer commitment to specific producers and regional identities, and general EC platforms show clear associations between rating patterns and price formation, suggesting an active role of reviews in shaping perceived value.　Taken together, these results support Hypothesis 2, demonstrating that brand meaning in the rice EC market is increasingly constructed through consumer experiences and post-purchase evaluations.

　　Based on these findings, three strategic implications for the rice industry can be identified.　First, flexible branding strategies tailored to channel-specific consumer characteristics are essential─for example, emphasizing reliability and consistency in specialty channels, while highlighting producer narratives and regional identity in channels where individuality is valued.　Second, consumer reviews should be regarded not merely as “word-of-mouth” but as mechanisms for co-creating brand meaning.　Therefore, encouraging detailed reviews and integrating Social Networking Service platforms can enhance active consumer participation in value formation.　Third, increasing transparency regarding certifications and production processes, expanding 1-2 kg package offerings, and optimizing total payment structures─including both item price and shipping costs─can simultaneously appeal to consumer demands for safety, freshness and convenience.　Overall, in an EC environment characterized by diverse purchasing channels and active redefinition of brand meaning by consumers, adopting flexible and strategic value propositions aligned with channel characteristics are crucial for securing competitive advantage in Japan’s rice market.

JEL Classification:D4, Q13

　　Following the relaxation of COVID-19 travel restrictions, the number of inbound tourists has rapidly recovered, surpassing 2019 levels.　However, this recovery has led to the concentration of tourists in specific urban areas, causing over-tourism issues, while many rural regions still struggle to attract sufficient visitors.　To address this regional disparity and promote sustainable tourism, it is crucial to quantitatively understand the determinants of where tourists choose to stay.　This study empirically analyzed the factors influencing the staying population of inbound tourists across 1,896 municipalities in Japan, utilizing location-based big data （KDDI Location Analyzer） from the entire year of 2023.　Multiple regression analysis was employed to examine the impact of socio-economic factors─such as population density, the number of accommodation employees and proximity to transport hubs─and various tourism resources, including World Heritage sites, National Treasures, hot spring resorts （onsen） and castles.　The analysis classified the data by visit frequency （first-time vs. repeaters）, time of day, visitor origin （Asia vs. Europe）, and region （Golden Route vs. Rural areas） to capture diverse tourist needs.

　　The results of the comprehensive analysis were as follows.　First, regarding the total staying population, basic infrastructure （population density and accommodation capacity） and proximity to international airports significantly increased the number of stays.　Among tourism resources, hot spring resorts （onsen） demonstrated a consistently strong positive influence.　Second, regarding visit frequency, repeat visitors exhibited a much higher affinity for stay-oriented resources like onsen compared to first-time visitors, who were more sensitive to transport accessibility.　Third, the analysis by time of day revealed a behavioral cycle where tourists visit attraction sites during the day and congregate in accommodation-dense areas at night.　Fourth, a distinct contrast was observed based on visitor origin:Asian tourists prioritized transport efficiency and airport access, whereas European tourists showed a marked preference for historical and cultural assets, such as World Heritage sites and castles.　Finally, the regional comparison indicates that while the Golden Route relies heavily on transportation convenience and historical-cultural assets, rural areas depend more on natural resources and stay-type tourism resources to attract visitors.　In addition, this study demonstrates that a combination of location-based big data and statistical models is an effective method for quantitatively verifying regional differences in the inbound staying population and their association with regional characteristics.　The results of this analysis provide useful basic information for formulating promotion initiatives, future tourism policy planning, and regional revitalization strategies.

JEL Classification:R50, Z30

　　Multi-country input-output tables quantitatively represent transaction flows across industries and countries and provide an important empirical basis for studying global value chains (GVCs) and regional economics.　In recent years, a trend toward “big government” has been observed in advanced economies such as the United States, where industrial policies are actively promoted.　Meanwhile, international trade relations have developed beyond bilateral transactions into multilateral, interdependent networks, and the importance of GVC studies using multi-country input-output tables is accordingly increasing.　To this end, we propose a new extended method that constructs minimum spanning trees (MSTs) representing transaction structures using Z-scores, visualizes them by incorporating GVC lengths and industry categories, and quantitatively evaluates the significance of nodes in terms of centrality measures.　In this paper, we call this method the pair-type MST method.

　　In the experimental evaluation of the proposed pair-type MST method, we conducted both qualitative and quantitative analyses using the World Input-Output Tables (WIOTs) available from the World Input-Output Database (WIOD) and the Inter-Country Input-Output (ICIO) tables provided by the Organisation for Economic Co-operation and Development (OECD).　In the quantitative analysis, we introduce new indicators such as GVC length, input coefficient centrality, and output coefficient centrality, and compared the industry-based MST with the country-based MST to examine structural differences.

　　The results confirm that the industry-node backbone structure is robust and stable.　As an implication for regional economic research, although trade relations among certain countries have changed significantly over the past two decades due to institutional transitions and other factors, the backbone structure among industries has remained stable, partly because of shifts in the roles of countries within the global trade network.

JEL Classification:C1, C5, F2

　　This study applied the hypothetical extraction method （HEM） to the 2015 Chubu Region multi-regional input-output table （comprising 45 sectors） to examine interregional linkages connecting Ishikawa Prefecture’s core industries:production machinery, textile products, electronic components and accommodations, with the Chubu Region.　Simulated removal of each sector revealed interregional trade flows and quantified economic dependencies between Ishikawa and other prefectures within the Chubu Region.　Manufacturing sectors （production machinery, textile products, and electronic components） exhibited strong interregional linkages with both neighboring prefectures in the Hokuriku area and more distant prefectures in the Tokai area.　By contrast and reflecting its reliance on region-specific services and cultural assets, the accommodation sector demonstrated a more localized impact.　We identified two distinct patterns of industrial impact:i） affected sectors were consistent across regions, and ii） impacts varied according to regional trade structures.　Ishikawa accounted for approximately 60% of the total production loss in each manufacturing sector, while the accommodation sector accounted for approximately 75%, thus indicating stronger local dependence.　Furthermore, the affected industries in other prefectures included both highly and less specialized sectors, with varying degrees of impact.　Considering the potential economic damage from large-scale disasters, the importance of incorporating interregional trade structures into disaster preparedness is underscored.　Moreover, extending the HEM analysis to other Chubu Prefectures can enhance understanding of cross-regional vulnerabilities.　This framework supports proactive planning for disaster mitigation, industrial development, and regional collaboration, ultimately contributing to more resilient and interconnected regional economies.

JEL Classification:C67, D57, R15

　　This study aims to examine the influence of seven key factors on population movement from coastal to inland regions in China:disposable income, unemployment rate, housing prices, and local government expenditures on education, healthcare, social security and other public services.　Using population movement data from the National Bureau of Statistics of China （2011;2021）, we apply a gravity model by comparing changes in these factors from 2010 to 2020.

　　The results are as follows.　First, regarding disposable income, no statistically significant effect on population migration was found in either coastal or inland regions in most models.　However, the coefficient for inland areas shifted from negative to positive, suggesting that rising income is gradually beginning to promote population inflow into inland regions.　Second, while an increase in the unemployment rate in coastal areas did not necessarily accelerate migration to inland areas, a rising unemployment rate in inland regions reduced utility and became a clear factor inhibiting population inflow in 2020.　Third, rising housing prices in inland areas were found to promote population inflow;however, this effect showed a slight weakening by 2020.　Fourth, in 2010, fiscal expenditures on education, healthcare, and social security in coastal areas helped suppress population outflow.　In 2020, educational expenditures in inland areas became a significant factor in promoting population inflow.　In contrast, the effects of healthcare and social security expenditures remained limited, suggesting that disparities in medical services and social security systems between regions persist.　By focusing on the changes between 2010 and 2020, the analysis more clearly demonstrates the positive impact of expanded fiscal expenditures in inland areas as a significant driver of population inflows.

JEL Classifications:C13, H51, H52, O18, R23

　　Edible insects have attracted attention as a potential source of sustainable food.　However, as in other developed countries, Japanese consumers have exhibited low acceptance of insect-based foods.　Existing studies on consumer preferences for edible insects have mainly focused on Europe and the United States, while evidence from Asia, Africa, and Latin America remains limited.　In particular, few studies have examined consumer willingness to pay (WTP) for insect-based foods or assessed the effectiveness of acceptance-enhancing strategies in Japan.　Improving consumer acceptance therefore requires an understanding of consumer preferences and WTP, as well as differentiation of insect-based foods from conventional products through attributes such as nutritional value.　To address these gaps, this study conducted an online survey incorporating a discrete choice experiment targeting Japanese consumers.　The analysis pursued two objectives:estimation of consumer WTP for snack products containing cricket powder and evaluation of the effect of nutritional information on WTP through random assignment to information and no-information groups.　Choice data were analyzed using a mixed logit model to account for preference heterogeneity.　The results showed that the marginal WTP for snack products containing cricket powder ranged from −108.5 to −76.6 yen relative to conventional snack products, indicating strong aversion to insect-based foods among Japanese consumers.　In contrast, nutritional information had no statistically significant effect on WTP, suggesting that health- and nutrition-related information alone is insufficient to mitigate negative perceptions or emotional responses.　This reflects a mismatch between the information provided and consumer needs, or the possibility that any positive informational effect is offset by the strongly negative baseline valuation of the product.　Overall, the findings suggest that expanding acceptance of insect-based foods in Japan requires a multifaceted approach beyond nutritional attributes alone.

JEL Classification:Q13, D12, C25