arXiv subjects

Yasuyuki Todo

Publications and source records attributed to Yasuyuki Todo.

6 recordsLinked to original sources

arXiv2026

Stock Price Responses to Firm-Level News in Supply Chain Networks

This study examines how positive and negative news about firms is associated with stock prices and whether these associations extend to firms' suppliers and clients connected through supply chain relationships, using large samples of publicly listed firms worldwide and in Japan. News sentiment is measured using FinBERT, a natural language processing model fine-tuned for financial texts, and supply chain links are identified from financial statements for global firms and from large-scale firm-level surveys for Japanese firms. We find that stock prices exhibit systematic associations with positive and negative news even before public disclosure. These associations are also observed for suppliers and clients before and after disclosure. In general, relative to the pre-disclosure period, post-disclosure associations are larger, with the difference concentrated around the time of public news disclosure. However, for Japanese firms, the post-disclosure associations for suppliers and clients are smaller than the pre-disclosure associations, in contrast to the pattern observed for firms outside Japan.

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arXiv2025

Beyond Firms and Industries: Shock Propagation through Establishment- and Product-Level Supply Chains

This paper investigates how the granularity of supply-chain data affects the propagation of economic shocks through production networks. Using newly constructed establishment-level supply chains with product-level information links for Japan, we simulate disruption dynamics under alternative definitions of network nodes and input classifications. We show that defining inputs at the product level generates substantially larger propagation effects than industry-based classifications, indicating that coarse industry measures overstate input substitutability and underestimate systemic vulnerability. While establishment-level networks generally amplify shock propagation relative to firm-level networks, this effect is quantitatively modest, reflecting opposing forces of increased network complexity and greater substitution possibilities. We further demonstrate that incorporating establishment-level geographic information is critical for assessing region-specific shocks, as firm-level networks tend to overstate the impact of shocks originating in major metropolitan areas. Overall, our results highlight the importance of granular information on products, establishments, and geography for accurately evaluating supply-chain resilience and systemic risk.

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arXiv2024

Interdependency and cascading failures in co-patenting and shareholding interfirm networks

This work analyses the interdependent link creation of patent and shareholding links in interfirm networks, and how this dynamics affects the resilience of such networks in the face of cascading failures. Using the Orbis dataset, we construct very large co-patenting and shareholding networks, globally as well as in terms of individual countries. Besides, we construct smaller overlap networks from those firm pairs which have both types of links between them, for nine years between 2008-2016. We use information theoretic measures, such as mutual information, active information storage, and transfer entropy, to characterise the topological similarities and shared topological information between the relevant co-patenting and shareholding networks. We then construct a cascading failure model, and use it to analyse the resilience of interdependent interfirm networks in terms of multiple failure characteristics. We find that there is relatively high level of mutual information between co-patenting networks and the shareholding networks from later years, suggesting that the formation of shareholding links is influenced by the existence of patent links in previous years. We also show that this influence becomes most apparent after a delay of four years between the formation of co-patenting links and shareholding links. Analysing the resilience of shareholding networks against cascading failures, we show that in terms of both mean downtime, and failure proportion of firms, certain countries have less resilient shareholding networks compared to other countries with significant economies. Based on our results, we postulate that an interfirm network model which considers multiple types of relationships together could be a to highlight important features of economic systems around the world.

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arXiv2021

Lockdowns need geographic coordination because of propagation of economic effects through supply chains

In order to prevent the spread of COVID-19, governments have often required regional or national lockdowns, which have caused extensive economic stagnation over broad areas as the shock of the lockdowns has diffused to other regions through supply chains. Using supply-chain data for 1.6 million firms in Japan, this study examines how governments can mitigate these economic losses when they are obliged to implement lockdowns. Through tests of all combinations of two-region lockdowns, we find that coordinated, i.e., simultaneous, lockdowns yield smaller GDP losses than uncoordinated lockdowns. Furthermore, we test practical scenarios in which Japan's 47 regions impose lockdowns over three months and find that GDP losses are lower if nationwide lockdowns are coordinated than if they are uncoordinated.

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arXiv2021

Do economic effects of the anti-COVID-19 lockdowns in different regions interact through supply chains?

To prevent the spread of COVID-19, many cities, states, and countries have `locked down', restricting economic activities in non-essential sectors. Such lockdowns have substantially shrunk production in most countries. This study examines how the economic effects of lockdowns in different regions interact through supply chains, a network of firms for production, simulating an agent-based model of production on supply-chain data for 1.6 million firms in Japan. We further investigate how the complex network structure affects the interactions of lockdowns, emphasising the role of upstreamness and loops by decomposing supply-chain flows into potential and circular flow components. We find that a region's upstreamness, intensity of loops, and supplier substitutability in supply chains with other regions largely determine the economic effect of the lockdown in the region. In particular, when a region lifts its lockdown, its economic recovery substantially varies depending on whether it lifts lockdown alone or together with another region closely linked through supply chains. These results propose the need for inter-region policy coordination to reduce the economic loss from lockdowns.

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arXiv2020

The propagation of the economic impact through supply chains: The case of a mega-city lockdown against the spread of COVID-19

This study quantifies the economic effect of a possible lockdown of Tokyo to prevent spread of COVID-19. The negative effect of the lockdown may propagate to other regions through supply chains because of shortage of supply and demand. Applying an agent-based model to the actual supply chains of nearly 1.6 million firms in Japan, we simulate what would happen to production activities outside Tokyo when production activities that are not essential to citizens' survival in Tokyo were shut down for a certain period. We find that when Tokyo is locked down for a month, the indirect effect on other regions would be twice as large as the direct effect on Tokyo, leading to a total production loss of 27 trillion yen in Japan, or 5.3% of its annual GDP. Although the production shut down in Tokyo accounts for 21% of the total production in Japan, the lockdown would result in a reduction of the daily production in Japan by 86% in a month.

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