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DOI： 10.1103/PhysRevResearch.7.013235

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DOI： 10.1038/s41598-024-63719-z

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The trade distance is an important constraining factor underpinning the emergence of social and economic interactions of complex systems. However, agent-based studies supported by the granular analysis of distances are limited. Here, we present a complexity method that places the actual geographical locations of individual firms in Japan at the epicentre of our research. By combining methods derived from network science together with information theory measures, and by using a comprehensive dataset of Japanese inter-firm business transactions, we evaluate the effects of spatial features on the structural patterns of the economy. We find that the normalised probability distributions of the distances between interacting firms obey a power law like decay concomitant with the sizes of firms and regions. Furthermore, small firms would reach large distances to become customers of large firms, while trading between either only small firms or only large firms tends to be at smaller distances. Furthermore, a time evolution analysis suggests a reduction in the overall average trading distances in last 20 years. Lastly, our analysis concerning the trading dynamics among prefectures indicates that the preference to trade with neighbouring prefectures tends to be more pronounced at rural regions as opposed to the larger central conurbations.

DOI： 10.3390/math12081244

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We develop a single two-layered model framework that captures and replicates both the statistical properties of the network as well as those of the intrinsic quantities of the agents. Our model framework consists of two distinct yet connected elements that were previously only studied in isolation, namely methods related to temporal network structures and those associated with money transport flows. Within this context, the network structure emerges from the first layer and its topological structure is transferred to the second layer associated with the money transactions. In this manner, we can explain how the micro-level dynamics of the agents within the network lead to the exogenous manifestation of the aggregated system statistical data en-wrapping the very same agents within the system. This is done by capturing the essential dynamics of collective motion in complex networks that enable the simultaneous emergence of tent-shaped distributions in growth rates within the agents, together with the emergence of scaling properties within the network in the study. We can validate the model framework and dynamics by applying these to the context of the real-world inter-firm trading network of firms in Japan and comparing the results of the statistical distributions at both network and agent levels in a temporal manner. In particular, we compare our results to the fundamental quantities supporting the seven empirical laws observed in data: the degree distribution, the mean degree growth rate over time, the age distribution of the firms, the preferential attachment, the sales distribution in steady states, their growth rates, their scaling relations generated by the model. We find these results to be nearly identical to the real-world data. The framework has the potential to be transformed into a forecasting tool to support decision-makers on financial and prudential policies.

DOI： 10.1038/s41598-024-54719-0

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Other Link： https://www.nature.com/articles/s41598-024-54719-0

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DOI： 10.1103/physrevresearch.6.013059

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Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevResearch.6.013059/fulltext

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<jats:title>Abstract</jats:title><jats:p>We analyze the time series of hashtag numbers of social media data. We observe that the usage distribution of hashtags is characterized by a fat-tailed distribution with a size-dependent power law exponent and we find that there is a clear dependency between the growth rate distributions of hashtags and size of hashtags usage. We propose a generalized random multiplicative process model with a theory that explains the size dependency of the fat-tailed distribution. Numerical simulations show that our model reproduces these size-dependent properties nicely. We expect that our model is useful for understanding the mechanism of fat-tailed distributions in various fields of science and technology.</jats:p>

DOI： 10.1038/s41598-023-49572-6

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The convenience store industry in Japan holds immense significance, making a thorough comprehension of customer purchase behaviour invaluable for companies aiming to gain insights into their customer base. In this paper, we propose a novel application of a Markov network model to simulate purchases guided by stopping probabilities calculated from real data. Each node in the Markov network represents different product categories available for purchase. Additionally, we introduce the concept of a "driving force," quantifying the influence of purchasing product A on the likelihood of purchasing product B, compared to random purchasing. For instance, our analysis reveals that the inclusion of nutrient bars in a purchase set leads to, on average, a 13% reduction in tobacco purchases compared to random patterns. To validate our approach, we compare the simulated macro-level purchase behaviours with real point of Sale (POS) data obtained from a prominent convenience store giant, 7-Eleven. The dataset is comprised of roughly 54 million receipts, in which we focus on the product categories existing in this dataset rather than individual products. Our model successfully replicates the purchase size distribution for 99.9% of all purchases and the purchase counts across various product categories, demonstrating its efficacy in capturing broad purchase patterns.

DOI： 10.1038/s41598-024-60752-w

DOI： 10.21203/rs.3.rs-3229845/v1

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High-resolution fecal pharmacokinetics are crucial for optimizing therapeutic design and evaluating gastrointestinal motility. However, empirical studies with detailed fecal concentration over time data remain limited. This study aims to characterize fecal pharmacokinetics through high-frequency sampling and parallelized fecal concentration quantification, establishing a simple pharmacokinetics model with physiologically interpretable parameters. We quantified vancomycin concentrations in fecal samples collected at a minimum interval of 4 hours from C57BL/6N mice following a single oral administration of either a low (1 mg/mL) or high (20 mg/mL) dose. Fecal concentrations gradually increased and exhibited an exponential decay, leading to the development of a compartmental model with an absorption phase. This simple model accurately fit the experimental data and provided physiological explanations for intra- and inter-individual pharmacokinetics variability. The results suggest that inter-individual differences in pharmacokinetics are attributable to fecal elimination capacity, which may be influenced by drug dosage via changes in gastrointestinal motility. Since the model predicts antibiotic concentrations within the gastrointestinal tract, it can be applied to fundamental studies investigating the effects of antibiotics on the gut microbiome and gastrointestinal motility.

DOI： 10.1101/2023.05.05.539495

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We introduce a new non-black-box method of extracting multiple areas in a high-dimensional big data space where data points that satisfy specific conditions are highly concentrated. First, we extract one-dimensional areas where the data that satisfy specific conditions are mostly gathered by using the Bayesian method. Second, we construct higher-dimensional areas where the densities of focused data points are higher than the simple combination of the results for one dimension, and then we verify the results through data validation. Third, we apply this method to estimate the set of significant factors shared in successful firms with growth rates in sales at the top 1% level using 156-dimensional data of corporate financial reports for 12 years containing about 320,000 firms. We also categorize high-growth firms into 15 groups of different sets of factors.

DOI： 10.3390/e25030488

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society ({APS})  

We propose a data-driven stochastic method that allows the simulation of a complex system's long-term evolution. Given a large amount of historical data on trajectories in a multi-dimensional phase space, our method simulates the time evolution of a system based on a random selection of partial trajectories in the data without detailed knowledge of the system dynamics. We apply this method to a large data set of time evolution of approximately one million business firms for a quarter century. Accordingly, from simulations starting from arbitrary initial conditions, we obtain a stationary distribution in three-dimensional log-size phase space, which satisfies the allometric scaling laws of three variables. Furthermore, universal distributions of fluctuation around the scaling relations are consistent with the empirical data.

DOI： 10.1103/physreve.106.064304

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Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevE.106.064304/fulltext

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The two-body stochastic dealer model is revisited to provide an exact solution to the average order-book profile using the kinetic approach. The dealer model is a microscopic financial model where individual traders make decisions on limit-order prices stochastically and then reach agreements on transactions. In the literature, this model was solved for several cases: an exact solution for two-body traders$$N=2$$and a mean-field solution for many traders$$N\gg 1$$. Remarkably, while kinetic theory plays a significant role in the mean-field analysis for$$N\gg 1$$, its role is still elusive for the case of$$N=2$$. In this paper, we revisit the two-body dealer model$$N=2$$to clarify the utility of the kinetic theory. We first derive the exact master-Liouville equations for the two-body dealer model. We next illustrate the physical picture of the master-Liouville equation from the viewpoint of the probability currents. The master-Liouville equations are then solved exactly to derive the order-book profile and the average transaction interval. Furthermore, we introduce a generalised two-body dealer model by incorporating interaction between traders via the market midprice and exactly solve the model within the kinetic framework. We finally confirm our exact solution by numerical simulations. This work provides a systematic mathematical basis for the econophysics model by developing better mathematical intuition.

DOI： 10.1007/s10955-022-03022-1

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Other Link： https://link.springer.com/article/10.1007/s10955-022-03022-1/fulltext.html

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

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During the COVID-19 pandemic, governments faced difficulties in implementing mobility restriction measures, as no clear quantitative relationship between human mobility and infection spread in large cities is known. We developed a model that enables quantitative estimations of the infection risk for individual places and activities by using smartphone GPS data for the Tokyo metropolitan area. The effective reproduction number is directly calculated from the number of infectious social contacts defined by the square of the population density at each location. The difference in the infection rate of daily activities is considered, where the ‘stay-out’ activity, staying at someplace neither home nor workplace, is more than 28 times larger than other activities. Also, the contribution to the infection strongly depends on location. We imply that the effective reproduction number is sufficiently suppressed if the highest-risk locations or activities are restricted. We also discuss the effects of the Delta variant and vaccination.

DOI： 10.1038/s41598-022-22420-9

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Other Link： https://www.nature.com/articles/s41598-022-22420-9

Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Physical Society of Japan  

We investigated information spreading on online social media, which is widely used in Japan. In particular, we constructed an index for information spreading on Twitter, focusing on the difference in network structure between fake news and real news. This index may enable us to extract the difference between fake and real news without text or demographic information.

DOI： 10.11316/butsuri.77.7_458

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DOI： 10.1038/s41598-022-13789-8

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DOI： 10.1038/s41598-022-13789-8

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Bursts and collective emotion have been widely studied in social physics field where researchers use mathematical models to understand human social dynamics. However, few researches recognize and separately analyze the internal and external influence on burst behaviors. To bridge this gap, we introduce a non-parametric approach to classify an interevent time series into five scenarios: random arrival, endogenous burst, endogenous non-burst, exogenous burst and exogenous non-burst. In order to process large-scale social media data, we first segment the interevent time series into sections by detecting change points. Then we use the rule-based algorithm to classify the time series based on its distribution. To validate our model, we analyze 27.2 million COVID-19 related comments collected from Chinese social media between January to October 2020. We adopt the emotion category called Profile of Mood States which consists of six emotions:Anger,Depression,Fatigue,Vigor,TensionandConfusion. This enables us to compare the burst features of different collective emotions during the COVID-19 period. The burst detection and classification approach introduced in this paper can also be applied to analyzing other complex systems, including but not limited to social media, financial market and signal processing.

DOI： 10.1038/s41598-022-07067-w

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Other Link： https://www.nature.com/articles/s41598-022-07067-w

Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.physrep.2021.10.005

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Focusing on the diffusion-localization transition, we theoretically analyzed a nonlinear gravity-type transport model defined on networks called regular ring lattices, which have an intermediate structure between the complete graph and the simple ring. Exact eigenvalues were derived around steady states, and the values of the transition points were evaluated for the control parameter characterizing the nonlinearity. We also analyzed the case of the Bethe lattice (or Cayley tree) and found that the transition point is 1/2, which is the lowest value ever reported.

DOI： 10.1007/s10955-022-02882-x

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Other Link： https://link.springer.com/article/10.1007/s10955-022-02882-x/fulltext.html

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Traders who instantly react to changes in the financial market and place orders in milliseconds are called high-frequency traders (HFTs). HFTs have recently become more prevalent and attracting attention in the study of market microstructures. In this study, we used data to track the order history of individual HFTs in the USD/JPY forex market to reveal how individual HFTs interact with the order book and what strategies they use to place their limit orders. Specifically, we introduced an 8-dimensional multivariate Hawkes process that included the excitations due to the occurrence of limit orders, cancel orders, and executions in the order book change, and performed maximum likelihood estimations of the limit order processes for 134 HFTs. As a result, we found that the limit order generation processes of 104 of the 134 HFTs were modeled by a multivariate Hawkes process. In this analysis of the EBS market, the HFTs whose strategies were modeled by the Hawkes process were categorized into three groups according to their excitation mechanisms: (1) those excited by executions; (2) those that were excited by the occurrences or cancellations of limit orders; and (3) those that were excited by their own orders.

DOI： 10.3390/e24020214

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To prevent the spread of the COVID-19 pandemic, governments in various countries have severely restricted the movement of people. The large amount of detailed human location data obtained from mobile phone users is useful for understanding the change of flow patterns of people under the effect of pandemic. In this paper, we observe the synchronized human flow during the COVID-19 pandemic using Global Positioning System data of about 1 million people obtained from mobile phone users. We apply the drainage basin analysis method which we introduced earlier for characterization of macroscopic human flow patterns to observe the effect of the spreading pandemic. Before the pandemic the afternoon basin size distribution has been approximated by an exponential distribution, however, the distribution of Tokyo and Sapporo, which were most affected by the first wave of COVID-19, deviated significantly from the exponential distribution. On the other hand, during the morning rush hour, the scaling law holds universally, i.e., in all cities, even though the number of moving people in the basin has decreased significantly. The fact that these scaling laws, which are closely related to the three-dimensionality structure of the city and the fractal structure of the transportation network, have not changed indicates that the macroscopic human flow features are determined mainly by the means of transport and the basic structure of cities which are invariant of the pandemic.

DOI： 10.1007/s41109-021-00416-0

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Other Link： https://link.springer.com/article/10.1007/s41109-021-00416-0/fulltext.html

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The Sigma-Pi structure investigated in this work consists of the sum of products of an increasing number of identically distributed random variables. It appears in stochastic processes with random coefficients and also in models of growth of entities such as business firms and cities. We study the Sigma-Pi structure with Bernoulli random variables and find that its probability distribution is always bounded from below by a power-law function regardless of whether the random variables are mutually independent or duplicated. In particular, we investigate the case in which the asymptotic probability distribution has always upper and lower power-law bounds with the same tail-index, which depends on the parameters of the distribution of the random variables. We illustrate the Sigma-Pi structure in the context of a simple growth model with successively born entities growing according to a stochastic proportional growth law, taking both Bernoulli, confirming the theoretical results, and half-normal random variables, for which the numerical results can be rationalized using insights from the Bernoulli case. We analyze the interdependence among entities represented by the product terms within the Sigma-Pi structure, the possible presence of memory in growth factors, and the contribution of each product term to the whole Sigma-Pi structure. We highlight the influence of the degree of interdependence among entities in the number of terms that effectively contribute to the total sum of sizes, reaching the limiting case of a single term dominating extreme values of the Sigma-Pi structure when all entities grow independently.

DOI： 10.3390/e23020241

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DOI： 10.3390/e23020168

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Detail observation of human locations became available recently by the development of information technology such as mobile phones with GPS (Global Positioning System). We analyzed temporal changes of global human flow patterns in urban regions based on mobile phones’ GPS data in 9 large cities in Japan. By applying a new concept of drainage basins in analogous to river flow patterns, we discovered several universal scaling relations. These include, the number of moving people in a drainage basin of diameter L is proportional to $$L^3$$ in the morning rush hour, which is surprisingly different from reasonable intuition of proportionality to the 2 dimensional area, $$L^2$$. We show that this unexpected 3 dimensional feature is related to the strong attraction of the city center to become a 3 dimensional structure due skyscrapers.

DOI： 10.1038/s41598-020-77163-2

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We propose the epsilon-tau procedure to determine up- and down-trends in a time series, working as a tool for its segmentation. The method denomination reflects the use of a tolerance level ε for the series values and a patience level τ in the time axis to delimit the trends. We first illustrate the procedure in discrete random walks, deriving the exact probability distributions of trend lengths and trend amplitudes, and then apply it to segment and analyze the trends of U.S. dollar (USD)/Japanese yen (JPY) market time series from 2015 to 2018. Besides studying the statistics of trend lengths and amplitudes, we investigate the internal structure of the trends by grouping trends with similar shapes and selecting clusters of shapes that rarely occur in the randomized data. Particularly, we identify a set of down-trends presenting similar sharp appreciation of the yen that are associated with exceptional events such as the Brexit Referendum in 2016.

DOI： 10.1371/journal.pone.0239494

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Foreign exchange rates movements exhibit significant cross-correlations even on very short time-scales. The effect of these statistical relationships become evident during extreme market events, such as flash crashes. Although a deep understanding of cross-currency correlations would be clearly beneficial for conceiving more stable and safer foreign exchange markets, the microscopic origins of these interdependencies have not been extensively investigated. This paper introduces an agent-based model which describes the emergence of cross-currency correlations from the interactions between market makers and an arbitrager. The model qualitatively replicates the time-scale vs. cross-correlation diagrams observed in real trading data, suggesting that triangular arbitrage plays a primary role in the entanglement of the dynamics of different foreign exchange rates. Furthermore, the model shows how the features of the cross-correlation function between two foreign exchange rates, such as its sign and value, emerge from the interplay between triangular arbitrage and trend-following strategies. In particular, the interaction of these trading strategies favors certain combinations of price trend signs across markets, thus altering the probability of observing two foreign exchange rates drifting in the same or opposite direction. Ultimately, this entangles the dynamics of foreign exchange rate pairs, leading to cross-correlation functions that resemble those observed in real trading data.

DOI： 10.1371/journal.pone.0234709

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Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

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Social media can be a double-edged sword for society, either as a convenient channel exchanging ideas or as an unexpected conduit circulating fake news through a large population. While existing studies of fake news focus on theoretical modeling of propagation or identification methods based on machine learning, it is important to understand the realistic propagation mechanisms between theoretical models and black-box methods. Here we track large databases of fake news and real news in both, Weibo in China and Twitter in Japan from different cultures, which include their traces of re-postings. We find in both online social networks that fake news spreads distinctively from real news even at early stages of propagation, e.g. five hours after the first re-postings. Our finding demonstrates collective structural signals that help to understand the different propagation evolution of fake news and real news. Different from earlier studies, identifying the topological properties of the information propagation at early stages may offer novel features for early detection of fake news in social media.

DOI： 10.1140/epjds/s13688-020-00224-z

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Other Link： http://link.springer.com/article/10.1140/epjds/s13688-020-00224-z/fulltext.html

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：{MDPI} {AG}  

<jats:p>From the viewpoint of statistical physics, ecosystems in the real world are very attractive targets of research as examples of far-from thermal equilibrium systems where various kinds of components are coming in and out continuously while keeping the whole systems quasi-stationary. As a fortunate example of a fully-observable ecosystem, we analyzed the comprehensive data of convenience stores where approximately 5% of the commodity species is replaced by new ones daily. The share of stores for each species fluctuates significantly; however, the entire distribution of shares is fairly stationary and follows the log-uniform distribution, that is, the power law distribution with exponent 0. We introduce an empirical time evolution model of shares and firstly deduce that the key mechanism of realizing this stationary distribution is random multiplicative diffusion in finite size spaces. Our model based on the general stochastic process is expected to be applicable to various dynamic systems, especially complex systems with highly nonlinear interactions.</jats:p>

DOI： 10.3390/e22030267

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：{MDPI} {AG}  

<jats:p>Complexity and information theory are two very valuable but distinct fields of research, yet sharing the same roots. Here, we develop a complexity framework inspired by the allometric scaling laws of living biological systems in order to evaluate the structural features of networks. This is done by aligning the fundamental building blocks of information theory (entropy and mutual information) with the core concepts in network science such as the preferential attachment and degree correlations. In doing so, we are able to articulate the meaning and significance of mutual information as a comparative analysis tool for network activity. When adapting and applying the framework to the specific context of the business ecosystem of Japanese firms, we are able to highlight the key structural differences and efficiency levels of the economic activities within each prefecture in Japan. Moreover, we propose a method to quantify the distance of an economic system to its efficient free market configuration by distinguishing and quantifying two particular types of mutual information, total and structural.</jats:p>

DOI： 10.3390/e22020206

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DOI： 10.1371/journal.pone.0225853

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Financial prices fluctuate as a results of the market impact of the flow of transactions between traders. Reciprocally, several studies of market microstructure have shown how decisions of individual traders or banks, implemented in their trading strategies, are affected by historical market information. However, little is known about the detailed processes of how such trading strategies at the micro level recursively affect future market information at the macro level. Using a special fined-grained dataset that allows us to track the complete trading behavior of specific banks in a U.S. dollar (USD) versus Japanese yen (JPY) market, we find that position management methods, defined as the number of units of USD bought or sold by banks against JPY, can be classified into two strategies: (1) banks increase their positions by trading in the same direction repeatedly, or (2) banks attempt to reduce their inventories by rapidly shifting their positions toward zero. We then demonstrate that their systematic position management strategies strongly influence future market prices, as demonstrated by our ability using this information to predict market prices about fifteen minutes in advance. Further, by detecting outlier trades, we reveal that traders seem to switch their strategies when they become aware of outlier trades. The evidence obtained here suggests that positions, which are a consequence of historical trading decisions based on the position management strategies of each bank, strongly influence future market prices, and we unravel how market prices at the macro level evolve through an interactive process involving the interaction between well-defined trading strategies at the micro level.

DOI： 10.1371/journal.pone.0220645

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The analysis of interfirm business transaction networks provides invaluable insight into the trading dynamics and economic structure of countries. However, there is a general scarcity of data available recording real, accurate and extensive information for these types of networks. As a result, and in common with other types of network studies - such as protein interactions for instance - research tends to rely on partial and incomplete datasets, i.e. subsets, with less certain conclusions. Here, we make use of unstructured financial and corporate reporting data in Japan as the base source to construct a financial reporting network, which is then compared and contrasted to the wider real business transaction network. The comparative analysis between these two rich datasets - the proxy, partially derived network and the real, complete network at macro as well as local structural levels - provides an enhanced understanding of the non trivial relationships between partial sampled subsets and fully formed networks. Furthermore, we present an elemental agent based pruning algorithm that reconciles and preserves key structural differences between these two networks, which may serve as an embryonic generic framework of potentially wider use to network research, enabling enhanced extrapolation of conclusions from partial data or subsets.

DOI： 10.1038/s41598-019-47490-0

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<jats:p>Waste reduction in retail is a fundamental problem for sustainability. Among waste reduction approaches such as recycling and donation, stock management based on demand estimation which leads to mitigate waste generation and maintain a high profit is expected to play an important role. However, demand estimation is generally difficult because fluctuations in sales are quite volatile, and stock-out leads to incomplete demand observation. Here, we propose data science solutions to estimate non-stationary demand with censored sales data including stock-outs and realize scientific stock management. Concretely, we extend a non-stationary time series analysis method based on Particle Filter to handle censored data, and combine it with the newsvendor problem formula to determine the optimal stock. Moreover, we provide a way of pricing waste reduction costs. A method to verify consistency between the statistical model and sales data is also proposed. Numerical analysis using actual Point-Of-Sales data in convenience stores shows food waste could be reduced several tenths percent keeping high profits in most cases. Specifically, in cases of foods disposed of frequently about 75% of working days, food waste decreases to about a quarter with the profit increases by about 140%. The way of pricing waste reduction costs tells new insights such as 27% waste reduction is achieved by 1% profit loss. Our method provides a practical solution for food waste reduction in the retail sector.</jats:p>

DOI： 10.3390/su11133589

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DOI： 10.1371/journal.pone.0213843

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DOI： 10.1088/1367-2630/ab0e55

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Other Link： http://iopscience.iop.org/article/10.1088/1367-2630/ab0e55/pdf

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DOI： 10.1007/s42001-019-00032-0

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<jats:p>We propose a parameter estimation method for non-stationary Poisson time series with the abnormal fluctuation scaling, known as Taylor’s law. By introducing the effect of Taylor’s fluctuation scaling into the State Space Model with the Particle Filter, the underlying Poisson parameter’s time evolution is estimated correctly from given non-stationary time series data with abnormally large fluctuations. We also developed a discontinuity detection method which enables tracking the Poisson parameter even for time series including sudden discontinuous jumps. As an example of application of this new general method, we analyzed Point-of-Sales data in convenience stores to estimate change of probability of purchase of commodities under fluctuating number of potential customers. The effectiveness of our method for Poisson time series with non-stationarity, large discontinuities and Taylor’s fluctuation scaling is verified by artificial and actual time series.</jats:p>

DOI： 10.3390/stats2010005

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DOI： 10.1088/1742-5468/aaf109

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Other Link： http://stacks.iop.org/1742-5468/2019/i=1/a=013403?key=crossref.49f3ee3044629730a35d9e3dc3b7a096

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DOI： 10.1007/s10015-018-0508-0

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Other Link： http://link.springer.com/article/10.1007/s10015-018-0508-0/fulltext.html

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

There is a growing interest to understand financial markets as ecological systems, where the variety of trading strategies correspond to that of biological species. For this purpose, transaction data for individual traders are studied recently as empirical analyses. However, there are few empirical studies addressing how traders submit limit and market order at the level of individual traders. Since limit and market orders are key ingredients finally leading to transactions, it would be necessary to understand what kind of strategies are actually employed among traders before making transactions. Here we demonstrate the variety of limit-order and market-order strategies and show their roles in the financial markets from an ecological perspective. We find these trading strategies can be well-characterized by their response pattern to historical price changes. By applying a clustering analysis, we provide an overall picture of trading strategies as an ecological matrix, illustrating that liquidity consumers are likely to exhibit high trading performances compared with liquidity providers. Furthermore, we reveal both high-frequency traders (HFTs) and low-frequency traders (LFTs) exhibit high trading performance, despite the difference in their trading styles; HFTs attempt to maximize their trading efficiency by reducing risk, whereas LFTs make their profit by taking risk.

DOI： 10.1371/journal.pone.0208332

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Authorship：Last author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society (APS)  

DOI： 10.1103/physreve.98.052317

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Other Link： http://harvest.aps.org/v2/journals/articles/10.1103/PhysRevE.98.052317/fulltext

Authorship：Last author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

We introduce a systematic method to estimate an economic indicator from the Japanese government by analyzing big Japanese blog data. Explanatory variables are monthly word frequencies. We adopt 1352 words in the section of economics and industry of the Nikkei thesaurus for each candidate word to illustrate the economic index. From this large volume of words, our method automatically selects the words which have strong correlation with the economic indicator and resolves some difficulties in statistics such as the spurious correlation and overfitting. As a result, our model reasonably illustrates the real economy index. The announcement of an economic index from government usually has a time lag, while our proposed method can be real time.

DOI： 10.3390/e20110852

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier {BV}  

DOI： 10.1016/j.physa.2018.06.002

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

DOI： 10.3390/e20070511

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41598-018-23675-x

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society  

DOI： 10.1103/PhysRevLett.120.138301

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0185712

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Authorship：Last author,　Corresponding author   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/e19080417

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0180863

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Publishing type：Research paper (scientific journal)   Publisher：Journal of the Physical Society of Japan  

DOI： 10.7566/jpscp.16.011013

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Publishing type：Research paper (scientific journal)   Publisher：Journal of the Physical Society of Japan  

DOI： 10.7566/jpscp.16.011004

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Publishing type：Research paper (scientific journal)   Publisher：Journal of the Physical Society of Japan  

DOI： 10.7566/jpscp.16.011011

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Publishing type：Research paper (scientific journal)   Publisher：Journal of the Physical Society of Japan  

DOI： 10.7566/jpscp.16.011003

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41598-017-05362-5

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1742-5468/aa6ddb

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DOI： 10.1371/journal.pone.0177652

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41598-017-00242-4

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Language：Japanese   Publisher：Japan Science and Technology Agency  

DOI： 10.1241/johokanri.60.512

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I028534383

Language：English   Publishing type：Research paper (scientific journal)  

Proceedings of the Asia-Pacific Econophysics Conference 2016 — Big Data Analysis and Modeling toward Super Smart Society — (APEC-SSS2016)

DOI： 10.7566/JPSCP.16.011014

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16K16016/

Language：English   Publishing type：Research paper (scientific journal)  

Proceedings of the Asia-Pacific Econophysics Conference 2016 — Big Data Analysis and Modeling toward Super Smart Society — (APEC-SSS2016)

DOI： 10.7566/JPSCP.16.011008

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16K16016/

Language：English   Publishing type：Research paper (scientific journal)  

Proceedings of the Asia-Pacific Econophysics Conference 2016 — Big Data Analysis and Modeling toward Super Smart Society — (APEC-SSS2016)

DOI： 10.7566/JPSCP.16.011012

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16K16016/

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevE.94.052317

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0157653

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Language：Japanese   Publisher：Japan Science and Technology Agency  

DOI： 10.1241/johokanri.59.271

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DOI： 10.1371/journal.pone.0142685

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevE.92.042811

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Language：English  

DOI： 10.1007/978-3-319-20591-5

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Language：English   Publisher：IEEE  

To examine number fluctuations in online social media, we focus on the daily appearances of adjectives, adnominal particles, and conjunctions in a Japanese blog space. We show that a non-trivial fluctuation scaling law exists between the standard deviation and the mean. When the number of appearances becomes larger, the standard deviation linearly increases. We introduce a random posting (RP) model, which is inspired by the random diffusion model, to reproduce the observed scaling law. We confirm that the RP model can estimate number fluctuations in a Japanese blog space from both analytical and simulated results.

DOI： 10.1109/ICNF.2015.7288568

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Physical Society  

DOI： 10.1103/PhysRevE.91.042815

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DOI： 10.1371/journal.pone.0119979

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Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0121443

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevE.91.042815

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer  

DOI： 10.1007/978-3-319-20591-5_18

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer  

DOI： 10.1007/978-3-319-20591-5_10

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Language：English   Publishing type：Part of collection (book)   Publisher：Springer  

DOI： 10.1007/978-3-319-20591-5_1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer  

DOI： 10.1007/978-3-319-20591-5_11

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-26310207/

Language：English   Publisher：Springer  

DOI： 10.1007/978-3-319-20591-5_3

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Language：Japanese   Publisher：日本シミュレーション学会  

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DOI： 10.1080/00949655.2013.781603

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DOI： 10.1371/journal.pone.0100338

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s10955-014-0956-4

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Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevLett.112.098703

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.69.2.2.0_156_2

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-24540395/

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-25750130/

Language：English  

DOI： 10.1002/cplx.21452

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physa.2012.10.020

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevE.87.012805

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.68.2.2.0_246_2

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.68.2.2.0_245_3

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.68.1.2.0_405_3

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Language：English   Publishing type：Research paper (international conference proceedings)  

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DOI： 10.3386/w18541

DOI： 10.1016/j.jimonfin.2021.102502_references_DOI_4LN1KJmwn31QN3Q50tInA7YSHyh

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media {LLC}  

DOI： 10.1140/epjst/e2012-01654-7

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.irfa.2011.06.010

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-24223003/

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1103/PhysRevLett.108.168701

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1367-2630/14/4/043034

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DOI： 10.1142/s2010194512007830

DOI： 10.1080/00949655.2013.781603_references_DOI_JDpVNwnMU0TacpgVRvNoTcnEi70

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Publishing type：Research paper (scientific journal)   Publisher：World Scientific Pub Co Pte Lt  

<jats:p> We analyze Japanese inter-firm network data showing scale-free properties as an example of a real complex network. The data contains information on money flow (annual transaction volume) between about 7000 pairs of firms. We focus on this money-flow data and investigate the correlation between various quantities such as sales or link numbers. We find that the flux from a buyer to a supplier is given by the product of the fractional powers of both sales with different exponents. This result indicates that the principle of detailed balance does not hold in the real transport of money; therefore, random walk type transport models such as PageRank are not suitable. </jats:p>

DOI： 10.1142/s2010194512007805

DOI： 10.1103/physreve.91.042815_references_DOI_1uXEyc2U1nSQSEC1gP9mNJK2DEI

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-24540395/

Language：Japanese   Publisher：The Japanese Society for Artificial Intelligence  

The dealer model is an agent based model that simulates the simplified dealer's behavior and satisfies various empirical laws of the foreign exchange markets by tuning major three parameters. In this study,we improve the dealer model to satisfy a newly established empirical law about widening of spread as a response to big market price changes. As a result when a big news occurs and the market becomes turbulent, this new model can reproduce broadening of distribution of price change.In a peculiar price change of official intervention in the foreign exchange market by Bank of Japan, this model can be used for estimation of strategies of intervention and responses of the market.

DOI： 10.1527/tjsai.27.365

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Language：Japanese   Publishing type：Research paper (other academic)  

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Publisher：IEEE  

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Other Link： http://dblp.uni-trier.de/db/conf/fusion/fusion2012.html#conf/fusion/YuraTTN12

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/14697681003792237

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Language：English  

DOI： 10.1143/ptps.194.202

DOI： 10.1371/journal.pone.0246884_references_DOI_DgKwlEOgcqmwZmpFBXy7gIT4m3x

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Other Link： http://dl.ndl.go.jp/info:ndljp/pid/10887536

Language：Japanese   Publisher：THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS  

DOI： 10.11509/isciesci.56.10_536

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I023997648

Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.67.1.2.0_380_1

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.67.2.2.0_236_2

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Language：Japanese   Publisher：THE INSTITUTE OF SYSTEMS, CONTROL AND INFORMATION ENGINEERS  

DOI： 10.11509/isciesci.56.10_517

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I023997597

Language：English   Publisher：Elsevier B.V.  

DOI： 10.1016/j.physa.2010.09.032

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Language：English  

DOI： 10.1109/icnf.2011.5994382

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/jpsgaiyo.66.2.2.0_276_4

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Language：English  

DOI： 10.1007/s11403-010-0066-6

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Other Link： http://link.springer.com/article/10.1007/s11403-010-0066-6/fulltext.html

Language：English  

DOI： 10.1007/s11403-010-0072-8

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1142/S0219635210002469

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Publisher：IOP Publishing  

We have analyzed the lifetime distributions of more than 0.7 million products sold across approximately 400 Japanese supermarkets. The distributions are well approximated by an exponential function for products with lifetimes longer than 1000 days, implying that the manufacturers' decisions about whether to continue production are purely random. However, the distributions tend to deviate from an exponential distribution for products with lifetimes shorter than 1000 days. Specifically, the distributions for food products exhibit a quicker decay in a short time scale, suggesting the existence of competing products during the initial stages of the product lifecycle. On the other hand, the distributions for toiletry products exhibit a slower decay in a short time scale.

DOI： 10.1088/1742-6596/221/1/012018

DOI： 10.1109/bigdata.2016.7840887_references_DOI_c8mr8abJy3XJKW75nrkXoQlkCp

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)   Publisher：物性研究刊行会  

この論文は国立情報学研究所の電子図書館事業により電子化されました。
ポスターセッション

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Other Link： http://hdl.handle.net/2433/169211

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

DOI： 10.1088/1742-6596/221/1/012012

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Language：English  

DOI： 10.1007/978-4-431-53853-0-5

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Language：English  

DOI： 10.1088/1742-6596/221/1/012015

DOI： 10.1527/tjsai.27.365_references_DOI_PTs4sDjf3LTO1RxwrEwueDLVFjV

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11403-010-0065-7

DOI： 10.48550/arxiv.0906.1744

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Other Link： http://link.springer.com/article/10.1007/s11403-010-0065-7/fulltext.html

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Japan Society for Industrial and Applied Mathematics  

Firms build business relationships during economic activities. We empirically analyze an inter-firm network consisting of about one million firms and four million directed links by evaluating PageRank and specifying network motifs. The topology of the network exhibits both small-world and scale-free properties. By comparing with randomized networks, we find that PageRank correlates significantly with the growth rate of the firm. By specifying network motifs, which are small subgraphs that occur more frequently than expected in a randomly generated network, we find that V-shaped triads are network motifs, while feedforward and feedback loop are anti-motifs. By defining roles in the subgraph according to structural equivalence, we also detect the significance profile of roles characterizing the industry sector. The taxonomy of industries obtained from the profiles is economically meaningful. These empirical findings provide a valuable insight into the relationship between the network structure and the economic function.

DOI： 10.11540/bjsiam.20.3_223

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

DOI： 10.1088/1742-6596/221/1/012013

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

DOI： 10.1088/1742-6596/221/1/011001

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DOI： 10.1103/PhysRevE.80.056110

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DOI： 10.1103/PhysRevE.79.051120

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DOI： 10.1143/ptps.179.1

DOI： 10.1080/00949655.2013.781603_references_DOI_Wk37HDmaKuPOLiDBjrXSAlmmvrG

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Publisher：Springer  

DOI： 10.1007/978-0-387-30440-3_223

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DOI： 10.1143/ptps.179.157

DOI： 10.1007/978-4-431-55390-8_2_references_DOI_O2pC5t5ZnRy6Kh8pivvMu1yR7XM

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I10225456

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DOI： 10.1143/ptps.179.71

DOI： 10.48550/arxiv.0905.2474

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I10225432

Language：English  

DOI： 10.1143/ptps.179.8

DOI： 10.1016/j.physrep.2021.10.005_references_DOI_HnfqK45fFtLkI46ESNFIkKQ1fyM

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I10225408

Language：English  

DOI： 10.1016/j.physa.2008.01.059

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media {LLC}  

DOI： 10.1140/epjb/e2008-00155-4

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Publisher：Springer Science and Business Media LLC  

We empirically investigate price fluctuations of yen-dollar exchange rate using the high-frequency data recorded in the electronic broking system for seven-year period. The distribution of quote price changes has symmetric fat-tails approximated by a power law; however, that of deal price is asymmetrical. The autocorrelation function and diffusion of price changes indicate that quote price exhibits anti-correlation feature in short time scale, whereas deal price is essentially uncorrelated. The bid-ask spread shows power-law distribution and long range temporal correlations similar to that observed in absoute price changes.

DOI： 10.1007/s11403-008-0033-7

DOI： 10.1016/j.irfa.2011.06.010_references_DOI_Il7aCMbJurlaGWSCe7X72CYAkMM

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Other Link： http://link.springer.com/article/10.1007/s11403-008-0033-7/fulltext.html

Language：English  

DOI： 10.1016/j.physa.2007.04.093

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DOI： 10.1016/j.physa.2007.02.027

DOI： 10.48550/arxiv.physics/0608099

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DOI： 10.1016/j.physa.2007.02.026

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DOI： 10.1016/j.physa.2007.04.098

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DOI： 10.1016/j.physa.2007.02.049

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Language：English  

DOI： 10.1016/j.physa.2007.04.094

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DOI： 10.1016/j.physa.2006.04.113

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DOI： 10.1016/j.physa.2006.04.041

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)   Publisher：物性研究刊行会  

近年,高頻度時系列データを用いた解析が進み,様々な市場の統計性が明らかになった.そこで,この統計性を再現する市場モデルの構築が期待されるが,そのようなモデルはまだない.本研究では,高安らによって提案された,閾値型のディーラーモデルを改良することにより,為替市場の統計性を幅広く再現するモデルを構築した.
この論文は国立情報学研究所の電子図書館事業により電子化されました。
研究会報告

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Other Link： http://hdl.handle.net/2433/110550

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I8029553

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physa.2005.08.079

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16540346/

Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physa.2005.04.026

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Language：English  

DOI： 10.1002/dac.722

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Language：English  

DOI： 10.1016/j.physa.2004.06.118

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Language：English  

DOI： 10.1002/ecja.1187

Scopus

CiNii Research

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physa.2003.10.006

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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CiNii Research

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I6833596

Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I6833628

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.physa.2004.06.145

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16540346/

Language：English   Publisher：Information Processing Society of Japan (IPSJ)  

We propose a new TCP optimization scheme for improving TCP performance over congested networks. The scheme, which we name LEAP, leaps a data segment for retransmission and transmits a new data segment when ACK segment loss is suspected. LEAP is based on judgment whether retransmission of a data segment is caused by a data segment loss or an ACK segment loss. According to our simulation results LEAP eliminates nearly all duplicated segments in heavily congested networks involving multiple connections. Additionally by avoiding such duplicated segments LEAP drastically decreases the number of total transmitted segments in each connection. Our results show that LEAP improves overall network utilization more than 120% higher than conventional TCP variants under congested networks.

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Other Link： http://id.nii.ac.jp/1001/00010881/

Publisher：Springer Japan  

DOI： 10.1007/978-4-431-53947-6_21

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Institute of Electronics, Information and Communication Engineers  

DOI： 10.24517/00007384

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Other Link： http://hdl.handle.net/2297/3004

Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English  

DOI： 10.1016/S0378-4371(02)01958-1

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Language：English  

DOI： 10.1016/S0378-4371(02)01881-2

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Language：English  

DOI： 10.1016/S0378-4371(03)00003-7

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Language：English   Publisher：Japanese Circulation Society  

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Springer Japan  

DOI： 10.1007/978-4-431-53947-6_3

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Language：English  

DOI： 10.1007/978-4-431-53947-6_23

DOI： 10.1007/978-3-319-08473-2_11_references_DOI_B8EQNXSxfWKjvemAfCaYf3DtSds

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Language：Japanese   Publisher：The Institute of Image Information and Television Engineers  

The integration of signal processing circuit in imase sensor, so called 'Vision Chip' is widely studied, but most of them don't aim at extracting image's meaning, which is often useful for the application of robot vision. In this paper, we propose a novel architecture for image sensor detecting the speed and the direction of moving point on focal plain. This architecture has an possibility to solve the direction dependency problem derived from matrix placement of pixels, and we consider a basic architecture for arbitrarily directional motion detection.

DOI： 10.11485/itetr.26.42.0_23

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Other Link： http://hdl.handle.net/2297/3532

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0378-4371(02)00598-8

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Language：English  

DOI： 10.1016/S0378-4371(02)00561-7

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Language：English  

DOI： 10.1007/978-4-431-66993-7_35

DOI： 10.48550/arxiv.cond-mat/0308365

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Publisher：Springer Japan  

DOI： 10.1007/978-4-431-66993-7_3

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Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English  

DOI： 10.1016/S0378-4371(00)00452-0

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Language：English  

DOI： 10.1142/s0218348x0000038x

DOI： 10.48550/arxiv.cond-mat/0006038

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Language：English  

DOI： 10.1016/S0378-4371(99)00499-9

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Language：English  

DOI： 10.1016/S0378-4371(99)00398-2

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Language：English  

DOI： 10.1016/S0378-4371(99)00076-X

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0378-4371(99)00086-2

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DOI： 10.1142/s0218348x9900030x

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DOI： 10.1142/s0218348x99000049

DOI： 10.1109/waina.2013.180_references_DOI_9VBG6PXF2OkxatPdVAmusNzPxGC

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Language：English  

DOI： 10.1016/S0375-9601(98)00176-5

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0378-4371(97)00659-6

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Language：Japanese   Publisher：The Physical Society of Japan  

DOI： 10.11316/butsuri1946.53.346

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I4480459

Language：English  

DOI： 10.1103/PhysRevLett.79.966

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Publisher：Springer Japan  

DOI： 10.1007/978-4-431-66862-6_16

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Language：English  

DOI： 10.1016/S0378-4371(96)00189-6

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/j.1525-1594.1996.tb04539.x

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Language：English  

DOI： 10.1209/epl/i1996-00305-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier {BV}  

DOI： 10.1016/0928-4680(95)00025-v

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1111/j.1525-1594.1995.tb02413.x

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Language：English  

DOI： 10.1142/S0217979294001676

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Language：English  

DOI： 10.1142/S0218348X93000885

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Language：English  

DOI： 10.1016/0378-4371(93)90591-Q

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English  

DOI： 10.1016/0378-4371(92)90122-7

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Language：English  

DOI： 10.1103/PhysRevA.46.782

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PubMed

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Language：English  

DOI： 10.1103/PhysRevA.45.8965

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DOI： 10.1103/PhysRevA.46.782

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Language：English  

DOI： 10.1007/bf01053751

DOI： 10.1143/jpsj.63.3629_references_DOI_9VW2rKKNUxcjPn206SUAo3fygAJ

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Other Link： http://link.springer.com/article/10.1007/BF01053751/fulltext.html

Language：English  

DOI： 10.1103/PhysRevA.42.7087

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Language：English  

DOI： 10.1103/PhysRevA.39.4345

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Language：English  

DOI： 10.1016/0375-9601(88)90507-5

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Language：English  

DOI： 10.1016/0375-9601(88)91040-7

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Language：Japanese  

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Language：Japanese  

DOI： 10.1241/johokanri.59.271

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Language：Japanese  

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Other Link： http://id.ndl.go.jp/bib/026736841

Language：Japanese  

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Language：Japanese  

CiNii Books

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Language：Japanese   Book type：Textbook, survey, introduction

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Total pages：viii, 256p   Language：Japanese  

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