Monetary Flow 貨幣の流れ


Monetary Flow


“First Demonstration Experiment for Energy-Trading System EDISON-X Using the XRP Ledger”

Yuichi Ikeda, Yu Ohki, Zelda Marquardt, Yu Kimura, Sena Omura 
and Emi Yoshikawa 
JPS Conf. Proc. 40, 011008 (2023) 

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   We developed a blockchain-based energy-trading system called EDISON-X to manage the buying and selling of electricity usage rights (i.e., tokens). Students buy UPX and SPX tokens to use electricity supplied from the utility company’s distribution lines and solar PV panels installed on the roof of the school building, respectively. In July 2022, 17 students from our school dormitory participated in an experiment to validate the operation of the EDISON-X system. Based on the results of this experiment, we describe an energy-trading system using blockchain technology for the effective usage of renewable energy. We developed topology and network science methodologies to understand the characteristics of energy trading. This study examined the hypothesis that market transactions become less active when “cavities” appear using topological data analysis. The preliminary results suggest that this hypothesis is plausible.


“Acquiring Semantic Mode Signal from Tweets of Cryptoassets”

Hiroshi Uehara, Wataru Souma and Yuichi Ikeda 
JPS Conf. Proc. 40, 011006 (2023)

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   This study proposes a method for detecting collective motions, the time series situation where dispersed information becomes inclined to a unique direction. Our proposal, Semantic mode signal, is distinctive among related methods in providing the situation with semantic contexts extracted from time series texts. Furthermore, the proposal is characterized by its applicability to high-dimensional word space with sparsity, such as numerous tweets. We applied the method to tweets concerning 19 cryptoassets. The empirical results indicated that the method appropriately detected the collective motions representing the contexts semantically coincident with the news events and the price trends, supporting the efficiency of our proposal.


“Hodge Decomposition of the Remittance Network on the XRP Ledger in the Price Hike of January 2018”

Yuichi Ikeda and Abhijit Chakraborty
JPS Conf. Proc. 40, 011004 (2023) 

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   This study analyzes the remittance transaction recorded on the XRP ledger for ETH and USD from July 2017 to Jun 2018, including the bubble period in early 2018. Using the Hodge decomposition, we estimate the “loop flow” in the international remittance of cryptoassets during the bubble period. We found characteristic differences between those fiat currencies and cryptoassets during the bubble period. For ETH, there was a significant increase in the loop flow during the cryptoasset price peak. This might be related to money laundering or arbitrage transaction. There was a slight increase in the loop flow for USD during the cryptoasset price peak.


“Embedding and Correlation Tensor for XRP Transaction Networks”

Abhijit Chakraborty, Tetsuo Hatsuda and Yuichi Ikeda 

JPS Conf. Proc, 40, 011003 (2023) 

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   Cryptoassets are growing rapidly worldwide. One of the large cap cryptoassets is XRP. In this article, we focus on analyzing transaction data for the 2017–2018 period that consist one of the significant XRP market price bursts. We construct weekly weighted directed networks of XRP transactions. These weekly networks are embedded on continuous vector space using a network embedding technique that encodes structural regularities present in the network structure in terms of node vectors. Using a suitable time window we calculate a correlation tensor. A double singular value decomposition of the correlation tensor provides key insights about the system. The significance of the correlation tensor is captured using a randomized correlation tensor. We present a detailed dependence of correlation tensor on model parameters.


“Projecting XRP Price Burst by Correlation Tensor Spectra of Transaction Networks”

Abhijit Chakraborty, Tetsuo Hatsuda and Yuichi Ikeda 

Scientific Reports, 13, 4718 (2023)

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   Cryptoassets are becoming essential in the digital economy era. XRP is one of the large market cap cryptoassets. Here, we develop a novel method of correlation tensor spectra for the dynamical XRP networks, which can provide an early indication for XRP price. A weighed directed weekly transaction network among XRP wallets is constructed by aggregating all transactions for a week. A vector for each node is then obtained by embedding the weekly network in continuous vector space. From a set of weekly snapshots of node vectors, we construct a correlation tensor. A double singular value decomposition of the correlation tensors gives its singular values. The significance of the singular values is shown by comparing with its randomize counterpart. The evolution of singular values shows a distinctive behavior. The largest singular value shows a significant negative correlation with XRP/USD price. We observe the minimum of the largest singular values at the XRP/USD price peak during the first week of January 2018. The minimum of the largest singular value during January 2018 is explained by decomposing the correlation tensor in the signal and noise components and also by evolution of community structure. 


“Cryptoasset networks: Flows and regular players in Bitcoin and XRP ”

Hideaki Aoyama, Yoshi Fujiwara, Yoshimasa Hidaka, Yuichi Ikeda 

PLOS ONE , 0273068

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  Cryptoassets flow among players as recorded in the ledger of blockchain for all the transactions, comprising a network of players as nodes and flows as edges. The last decade, on the other hand, has witnessed repeating bubbles and crashes of the price of cryptoassets in exchange markets with fiat currencies and other cryptos. We study the relationship between these two important aspects of dynamics, one in the bubble/crash of price and the other in the daily network of crypto, by investigating Bitcoin and XRP. We focus on “regular players” who frequently appear on a weekly basis during a period of time including bubble/crash, and quantify each player’s role with respect to outgoing and incoming flows by defining flow-weighted frequency. During the most significant period of one-year starting from the winter of 2017, we discovered the structure of three groups of players in the diagram of flow-weighted frequency, which is common to Bitcoin and XRP in spite of the different nature of the two cryptos. By examining the identity and business activity of some regular players in the case of Bitcoin, we can observe different roles of them, namely the players balancing surplus and deficit of cryptoassets (Bal-branch), those accumulating the cryptoassets (In-branch), and those reducing it (Out-branch). Using this information, we found that the regime switching among Bal-, In-, Out-branches was presumably brought about by the regular players who are not necessarily dominant and stable in the case of Bitcoin, while such players are simply absent in the case of XRP. We further discuss how one can understand the temporal transitions among the three branches. 

 暗号資産は、すべての取引についてブロックチェーンの台帳に記録され、プレイヤーをノード、フローをエッジとするネットワークで構成され、プレイヤー間でフローします。一方、この10年間は、不換紙幣や他の暗号との交換市場において、暗号資産の価格がバブルと暴落を繰り返していることが目撃されている。我々はBitcoinとXRPを調査することで、価格のバブル・クラッシュと暗号の日常的なネットワークにおけるダイナミクスという、この2つの重要な側面の関係を研究している。バブル/クラッシュを含む期間に週単位で頻繁に現れる「常連プレーヤー」に注目し、フロー加重頻度を定義することで、各プレーヤーの流出・流入フローに関する役割を定量化する。2017年冬から1年間の最も大きな期間において、ビットコインとXRPという異なる性質を持つ暗号でありながら、共通する3つのグループのプレイヤーの構造をフロー・ウェイト・フリークエンスの図に見出すことが出来ました。ビットコインの場合、一部の常連プレイヤーの身元や業務内容を調べることで、暗号資産の余剰と不足のバランスを取るプレイヤー(Bal-branch)、暗号資産を蓄積するプレイヤー(In-branch)、それを減らすプレイヤー(Out-branch)という異なる役割を観察することができます。これらの情報を用いて、Bal-, In-, Out-branch間の体制転換は、Bitcoinの場合は必ずしも支配的で安定的ではない正規のプレーヤーによってもたらされたと推定されますが、XRPの場合はそのようなプレーヤーが単に存在しないことが分かりました。さらに、3つのブランチの間の時間的な遷移をどのように理解したらよいかを考察する。

“Regional economic integration via detection of circular flow in international value-added network ”

Sotaro Sada, Yuichi Ikeda, 
PLOS ONE  16(8): e0255698 , 

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 Global value chains are formed through value-added trade, and some regions promote economic integration by concluding regional trade agreements to promote these chains. However, it has not been established to quantitatively assess the scope and extent of economic integration involving various sectors in multiple countries. In this study, we used the World Input–Output Database to create a cross-border sector-wise network of trade in value-added (international value-added network) covering the period of 2000–2014 and evaluated them using network science methods. By applying Infomap to the international value-added network, we confirmed two regional communities: Europe and the Pacific Rim. We applied Helmholtz–Hodge decomposition to the value-added flows within the region into potential and circular flows, and clarified the annual evolution of the potential and circular relationships between countries and sectors. The circular flow component of the decomposition was used to define an economic integration index. Findings confirmed that the degree of economic integration in Europe declined sharply after the economic crisis in 2009 to a level lower than that in the Pacific Rim. The European economic integration index recovered in 2011 but again fell below that of the Pacific Rim in 2013. Moreover, sectoral economic integration indices suggest what Europe depends on Russia in natural resources makes the European economic integration index unstable. On the other hand, the indices of the Pacific Rim suggest the steady economic integration index of the Pacific Rim captures the stable global value chains from natural resources to construction and manufactures of motor vehicles and high-tech products. 


“Location-sector analysis of international profit shifting on a multilayer ownership-tax network”

T. Nakamoto, O. Rouhban, Y. Ikeda, 
Evolutionary and Institutional Economics Review, 17, 219-241, 2020/01

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Currently all countries including developing countries are expected to utilize their own tax revenues and carry out their own development for solving poverty in their countries. However, developing countries cannot earn tax revenues like developed countries partly because they do not have effective countermeasures against international tax avoidance. Our analysis focuses on treaty shopping among various ways to conduct international tax avoidance because tax revenues of developing countries have been heavily damaged through treaty shopping. To analyze the location and sector of conduit firms likely to be used for treaty shopping, we constructed a multilayer ownership-tax network and proposed multilayer centrality. Because multilayer centrality can consider not only the value flowing in the ownership network but also the withholding tax rate, it is expected to grasp precisely the locations and sectors of conduit firms established for the purpose of treaty shopping. Our analysis shows that firms in the sectors of Finance and Insurance and Wholesale and Retail trade etc. are involved with treaty shopping. We suggest that developing countries make a clause focusing on these sectors in the tax treaties they conclude. 


“Identification of Key Companies for International Profit Shifting in the Global Ownership Network”

T. Nakamoto, A. Chakraborty, Y. Ikeda
Applied Network Science, 4, 58, 1-26,

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  In the global economy, the intermediate companies owned by multinational corporations (MNCs) have become important players in policy issue, influencing the international profit shifting and diversion of foreign direct investment (FDI). The purpose of this analysis is to identify and analyze high-risk intermediate companies used for international profit shifting. To achieve this aim, we propose a model that focuses on the structure of MNC’s ownership of each affiliate. On the basis of the information in the Orbis database, we constructed the Global Ownership Network (GON) to reflect the relationship between MNCs and intermediate companies. Moreover, we analyzed large MNCs listed in Fortune Global 500. In this analysis, we confirmed the validity of this model by identifying affiliates playing an important role in international tax avoidance. We found that intermediate companies are mainly based in the Netherlands and the United Kingdom, etc., and these companies are located in the jurisdictions favorably to treaty shopping. And it was found that such key companies are concentrated in the IN component of the bow-tie structure, which is the giant weakly connected component with the GON. Therefore, this clarifies that the key companies are geographically located in specific jurisdictions and concentrates on the specific GON components. The key companies are located in the areas that facilitate treaty shopping. Depending on the location of the MNCs, a difference is remarked in the jurisdiction where key companies are located.

 世界経済において、多国籍企業(MNC)が所有する中間企業は、国際的な利益移転や外国直接投資(FDI)の転用に影響を与え、政策問題の重要なプレーヤーとなっている。本分析の目的は、国際的な利益移転に利用されるリスクの高い中間企業を特定し、分析することである。この目的を達成するために、多国籍企業の各関連会社の所有構造に着目したモデルを提案する。Orbisデータベースの情報を基に、多国籍企業と中間企業の関係を反映したグローバル・オーナーシップ・ネットワーク(GON)を構築した。さらに、Fortune Global 500に上場している大規模多国籍企業を分析した。この分析では、国際的な租税回避に重要な役割を果たしている関連会社を特定することで、このモデルの妥当性を確認した。その結果、中間企業は主にオランダや英国等に拠点を置き、これらの企業は条約ショッピングに有利な国・地域に所在していることが判明した。そして、そのようなキー企業は、GONとの巨大な弱接続構成要素であるボウタイ構造のIN構成要素に集中していることが判明した。したがって、このことは、キー企業が地理的に特定の管轄区域に位置し、特定のGON構成要素に集中していることを明らかにしている。キー企業は、条約ショッピングを容易にする地域に位置している。多国籍企業の所在地によって、キーカンパニーが所在する管轄区域に違いが生じる。

“Identification of conduit jurisdictions and community structures in the withholding tax network”

T. Nakamoto, Y. Ikeda, 
Evolutionary and Institutional Economics Review, 15, 2, 477-493, 2018/12

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  Due to economic globalization, international tax avoidance has emerged as a well-known global issue. To contribute to providing the solution of international tax avoidance, we tried to investigate which part of the network is vulnerable. Specifically, focusing on treaty shopping, which is one of the international tax avoidance schemes, we attempt to find which jurisdictions are likely to be used for treaty shopping from the viewpoint of tax rates and reveal the relationships between jurisdictions used for treaty shopping and the others. For that purpose, based on withholding tax rates imposed on dividends, interest, and royalties, we produced the withholding tax network expressed as weighted graphs, computed the centralities and detected the communities. As a result, we identified the jurisdictions used for treaty shopping and pointed out that there are community structures. The results of our study suggested that fewer jurisdictions need to introduce more regulations for the prevention of treaty shopping worldwide.


" Dynamic relationship between XRP price and correlation tensor spectra of the transaction network"
Abhijit Chakraborty, Tetsuo Hatsuda and Yuichi Ikeda
Journal Physica A: Statistical Mechanics and its Applications
arXiv: 2309.05935


"Reconstruction of Interbank Network using Ridge Entropy Maximization Model"
Y. Ikeda, H. Takeda,
Journal of Economic Interaction and Coordination

中央大学企業研究所, 研究叢書 第42号,

“Complex correlation approach for high frequency financial dataComplex correlation approach for high frequency financial data”
M. Wilinski, Y. Ikeda, H. Aoyama,
Journal of Statistical Mechanics: Theory and Experiment, 023405-023405,


Commodity Flow



Monetary Flow



Human Flow



Decarbonized energy system



Economic Collective Motions