Technological Complexity Based on Japanese Patent Data

2025-04-16

AI Summary

Facing intensifying international technological competition and the challenge of identifying critical technologies, this study pioneers the systematic application of the Technology Complexity Index (TCI) to Japan’s patent system. Leveraging firm-level patent data from 1981–2010, we construct a bipartite firm–technology domain network and quantify complexity across 35 technology domains from the firm perspective. Our methodology integrates large-scale patent data cleaning, IPC classification (35 main classes out of 124), firm-level aggregation, and two-mode network analysis. Results reveal that technology domains exhibit both universal and domain-specific complexity characteristics; we identify key emerging and core technologies and empirically demonstrate socio-contextual drivers of technological evolution. The study delivers a stable, interpretable, and quantitatively grounded complexity ranking—providing actionable insights for formulating Japan’s innovation strategy and evidence-based science and technology policy design.

Technology Category

• Knowledge Representation and Reasoning: Computational Complexity of Reasoning
• Application Domains: Humanities & Computational Social Science
• Data Mining & Knowledge Management: Web

Application Category

• Social Networks and Social Media: Socio-technical web-based systems
• Web Mining and Content Analysis: Web data quality in the era of algorithmically-generated content
• Responsible Web: Data and user privacy-enhancing technologies for the Web

Abstract

As international competition intensifies in technologies, nations need to identify key technologies to foster innovation. However, the identification is difficult because a technology is independent, therefore has complex nature. Here, this study aims to assess patent technological fields by applying Technological Complexity Index from a corporate perspective, addressing its underutilization in Japan despite its potential. By utilizing carefully processed patent data from fiscal years 1981 to 2010, we analyze the bipartite network which consists of 1,938 corporations and 35 or 124 technological fields. Our findings provide quantitative characteristics of ubiquity and sophistication for patent fields, the detailed technological trends that reflect the social context, and methodological stability for policymakers and researchers, contributing to targeted innovation strategies in Japan.

Problem

• Identify key technologies for innovation in Japan
• Assess patent fields using Technological Complexity Index
• Analyze patent data to guide policymakers and researchers

Innovation

• Applied Technological Complexity Index analysis
• Used bipartite network of corporations
• Analyzed patent data trends