Search Results - "Ishikawa, Atushi"

Generation of individual daily trajectories by GPT-2 by Mizuno, Takayuki, Fujimoto , Shouji, Ishikawa , Atushi

“…We propose a new method to convert individual daily trajectories into token time series by applying the tokenizer “SentencePiece” to a geographic space divided…”
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Quasi-Static Variation of Power-Law and Log-Normal Distributions of Urban Population by Ishikawa, Atushi, Fujimoto, Shouji, Ramos, Arturo, Mizuno, Takayuki

“…We analytically derived and confirmed by empirical data the following three relations from the quasi-time-reversal symmetry, Gibrat’s law, and the non-Gibrat’s…”
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Copula-Based Synthetic Data Generation in Firm-Size Variables by Fujimoto, Shouji, Ishikawa, Atushi, Mizuno, Takayuki

“…Using the survival Clayton copula, we propose a method for generating synthetic data on such firm-size variables as operating revenues and the number of…”
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Interpolation of non-random missing values in financial statements’ big data using CatBoost by Fujimoto, Shouji, Mizuno, Takayuki, Ishikawa, Atushi

“…Financial statements’ big data have the characteristics of “Incompleteness” and “Nonrepresentative”. In this paper, employing the world’s largest commercial…”
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The uniqueness of firm size distribution function from tent-shaped growth rate distribution by Ishikawa, Atushi

“…Employing profits data of Japanese firms in 2003 and 2004, we report the proof that a Non-Gibrat's law in the middle scale region of profits is unique under…”
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Statistical Properties of Labor Productivity Distributions by Ishikawa, Atushi, Fujimoto, Shouji, Mizuno, Takayuki

“…We employed the latest version of the world’s largest corporate financial database and identified the following three statistical properties of the physical…”
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Employee Number Dependence in Labor Productivity Distribution by Ishikawa, Atushi, Mizuno, Takayuki, Fujimoto, Shouji

“…Using data from Japanese and French firms in the 2020 edition of ORBIS, the world’s largest commercial database, we define labor productivity to be the…”
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Annual change of Pareto index dynamically deduced from the law of detailed quasi-balance by Ishikawa, Atushi

“…Employing data on the assessed value of land in 1983–2005 Japan, we investigate the dynamical behavior in the high scale region of non-equilibrium systems…”
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Initial Value Dependence of Urban Population's Growth-Rate Distribution and the Long-Term Growth by Ishikawa, Atushi, Fujimoto, Shouji, Ramos, Arturo, Mizuno, Takayuki

“…This paper uses census municipal population data for the United States, Italy, and Spain to analyze the statistical properties of their 10-year growth…”
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Pareto index induced from the scale of companies by Ishikawa, Atushi

“…Employing profits data of Japanese companies in 2002 and 2003, we confirm that Pareto's law and the Pareto index are derived from the law of detailed balance…”
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Analytical Derivation of Power Laws in Firm Size Variables from Gibrat’s Law and Quasi-inversion Symmetry: A Geomorphological Approach by Ishikawa, Atushi, Fujimoto, Shouji, Mizuno, Takayuki, Watanabe, Tsutomu

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The emergence of different tail exponents in the distributions of firm size variables by Ishikawa, Atushi, Fujimoto, Shouji, Watanabe, Tsutomu, Mizuno, Takayuki

“…We discuss a mechanism through which inversion symmetry (i.e., invariance of a joint probability density function under the exchange of variables) and Gibrat’s…”
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Statistical law observed in inactive rate of firms by Ishikawa, Atushi, Fujimoto, Shouji, Mizuno, Takayuki

“…In this study, we observe the dependence of the inactive rate of firms on firm-size variables: total revenue, net income, total assets, and net assets. This is…”
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Shape of growth-rate distribution determines the type of Non-Gibrat’s Property by Ishikawa, Atushi, Fujimoto, Shouji, Mizuno, Takayuki

“…In this study, the authors examine exhaustive business data on Japanese firms, which cover nearly all companies in the mid- and large-scale ranges in terms of…”
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Derivation of the distribution from extended Gibrat's law by Ishikawa, Atushi

“…Employing profits data of Japanese companies in 2002 and 2003, we identify the non-Gibrat's law which holds in the middle profits region. From the law of…”
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Firm Growth Function and Extended-Gibrat’s Property by Watanabe, Tsutomu, Mizuno, Takayuki, Fujimoto, Shouji, Ishikawa, Atushi

“…We analytically show that the logarithmic average sales of firms first follow power-law growth and subsequently follow exponential growth, if the growth-rate…”
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Quasi-Statically Varying Power-Law and Log-Normal Distributions in the Large and the Middle Scale Regions of Japanese Land Prices by Ishikawa, Atushi

“…Employing data on the assessed value of land in 1974–2008 Japan, we exhibit a quasi-statically varying distributions not only in the large scale region but…”
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Power-Law and Log-Normal Distributions in Temporal Changes of Firm-Size Variables by Ishikawa, Atushi

“…In this paper the author shows that signed temporal changes of firm size variables follow the power-law for large changes; while, for middle changes a…”
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Long-term firm growth properties derived from short-term laws of sales and number of employees in Japan and France by Ishikawa, Atushi, Fujimoto, Shouji, Mizuno, Takayuki, Watanabe, Tsutomu

“…In Japan, we observed rapid power law growth in the first 10 years of the existence of firms and subsequent slow exponential growth on their ages not only in…”
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A new method for measuring tail exponents of firm size distributions by Fujimoto, Shouji, Ishikawa, Atushi, Mizuno, Takayuki, Watanabe, Tsutomu

“…The authors propose a new method for estimating the power-law exponents of firm size variables. Their focus is on how to empirically identify a range in which…”
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