Abstract: Based on the analytical framework of the expansion of technological prospects, two-dimensional structural transformation of economic complexity, and breakthrough of the "stagnation trap" of middle-income countries, this paper constructs a set of network indicators reflecting the evolution characteristics of product space structure. Using the export products data of 133 countries from 1962 to 2019 obtaining: (1) Measuring the " Prospect coefficient for technological upgrading of Potential Advantageous Products" yields information on the national capability accumulation, which is correlated with the country's economic complexity to obtain a visualization of the non-linear evolution of technological prospects. The "S" curve formed shows that middle-income countries are facing a jump in capability from irrelevance to relevance between the expansion of technological prospects and economic complexity, and only very few countries can cross the sparse zone in the middle part of the curve, climbing from the bottom to the top of the curve, and ranking among developed countries. China, like Japan and South Korea, is one of the few countries that have caught up and moved out of the sparse zone in the middle of the curve. (2) On the basis of measuring the two-dimensional structural indicators of product diversity and heterogeneity in the economic complexity of 133 countries, a comparison between China, Japan, and South Korea reveals that China is currently undergoing a two-dimensional structural transformation of economic complexity, similar to what happened in Japan and South Korea when they broke through the "stagnation trap" and entered the high-income countries, and the product heterogeneity index has been greatly improved during the deep structural adjustment, but the two-dimensional transformation from product diversity to heterogeneity has not been completed yet. (3) By visualizing the four-phase evolutionary characteristics of China, Japan and South Korea's product space and targeting the progressive capacity of government policies behind it, we can provide a decision-making basis for China to successfully complete the two-dimensional structural transformation, expand its technological prospects and break through the "stagnation trap" to realize high-quality development under the conditions of the new round of technological revolution and industrial change by drawing on the experience of Japan and South Korea in grasping the "second window of opportunity" for the digital economy and green development technology.

摘要： 基于技术前景拓展、经济复杂度的二维结构转换与中等收入国家“停滞陷阱”突破的分析框架，构筑了一套反映产品空间结构演化特征的网络指标，利用1962-2019年133个国家的出口产品数据：（1）测度“潜在比较优势产品技术升级前景系数”由此获得国家能力积累的信息，与国家经济复杂度关联得到技术前景非线性演化可视图。其形成的“S”曲线显示，中等收入国家面临技术前景拓展与经济复杂度由不相关到相关的能力跳跃过程，只有极少国家能够跨越该曲线中段稀疏带，技术演化从曲线底部攀升到顶部、跻身发达国家梯队。中国与日本、韩国一样属于少数技术追赶型、走出曲线中段稀疏带的国家；（2）在测度133个国家经济复杂度中产品多样性与异质性二维结构指标的基础上，通过中日韩比较发现，中国目前正在经历经济复杂度的二维结构转换，与日韩突破“停滞陷阱”进入高收入国家时的情景类似，深度的结构调整中产品异质性指数已经大幅度提高，但还没有完成产品多样性到异质性的二维转换；（3）通过可视化中日韩产品空间网络的四期演化特征，靶向其背后的政府政策递进能力，为在新一轮科技革命和产业变革条件下，借鉴日韩经验抓住数字经济与绿色发展技术“第二机会窗口”，中国顺利完成二维结构转换、拓展技术前景、突破“停滞陷阱”实现高质量发展提供决策依据。