Are there Schumpeterian waves of innovations?
回应了对创新聚集现象实证证据的批评，通过分析长期创新样本发现19世纪中期前创新浪潮证据不足，但此后出现两次重大创新长波，领先经济长波约10-15年，且t检验确认其与随机波动显著不同。
This paper responds to a recent criticism of the empirical evidence of bunching of innovations. An examination of various long-run innovation samples shows that there is indeed very poor evidence of innovation waves in the time before the mid-19th century. Thereafter, however, two long waves of major innovations occur, both having a lead of approximately 10-15 years over the economic long wave as identified in an earlier study. A t-test confirms that these waves can be clearly distinguished from random fluctuations. In the final section some suggestions for further research are outlined.