1969年分享第一个诺贝尔经济学奖的弗里希,以噪声驱动周期模型主导了宏观经济学和计量经济学的发展。实际上,弗里希在1933年非正式会议上构想的模型,早在1930~1945年就被物理学的研究所否定,文章也从未在计量经济学期刊上正式发表。奇怪的是,弗里希本人从1934年起就对该模型保持沉默,连他的诺奖演说也不置一词。用弗里希模型分析美国实际GDP数据,也得不到持续的经济周期。破解弗里希模型之谜,可以看清经济周期理论中周期外生论和内生论的争论,关系到经济学界均衡论和演化论的不同视角。非线性动力学的最新成果告诉我们,只有非线性振子才能产生持续的经济周期,也就是熊彼特提出的生物钟。 Frisch, who shared the first Nobel Prize for Economics in 1969, dominates the development of macroeconomics and econometrics with a noise-driven cycle model. In fact, the model Fritsch envisioned at the 1933 informal meeting was rejected by the Institute of Physics as early as 1930-1945, and the article was never officially published in the journal Econometrics. Curiously, Frisch himself has been silent on the model since 1934, and he does not even include his Nobel Prize speech. Analysis of real GDP data in the United States using the Forsch model also lacks a sustained economic cycle. To solve the puzzle of the Frisch model, we can see the debate about the cycle exogenous and endogenous theories in the economic cycle theory and the different perspectives of the equilibrium theory and evolution theory of the economic circle. The latest results of nonlinear dynamics tell us that only the nonlinear oscillator can produce a continuous economic cycle, that is, the biological clock proposed by Schumpeter.