Does patent data reveal successive technological revolutions and emerging trends?
Core argument: Patent data spanning 1842–2022 tracks successive technological revolutions, with railroads dominating the early 1800s and peaking again around 1900 during steel retrofitting.
The evolution of technology from 1842 to 2022 is vividly reflected in patent data, highlighting key technological revolutions. Railroads dominated the early 1800s, peaking again with steel retrofitting around 1900. The Age of Steel aligned with mass electrification, while the 1920s saw the automobile transform infrastructure. The late-1950s marked the onset of the Age of Information with circuitry, further accelerated by the internet in the late-1990s. By clustering patents into broad categories, we observe shifts in patent shares, focusing on the rate of change to identify trending technologies. This approach reveals how innovations like the internal combustion engine and internet have driven economic transformation, underscoring the importance of investing in emerging technologies to sustain growth and competitiveness.



Steve Comment: “…Read the underlying OECD report the blog post was based on, in terms of your question about what they meant by“…PIAAC test scores are regressed on matched PISA test scores and mean years of schooling. The estimation results show that the elasticity of the stock of human capital with respect to the quality of education is three to four times larger than for the quantity of education…”in their blog post (Note here STS is their “Transformed Student Test Score Series”)To capture quantity aspects, mean years of schooling (MYS) are added, on top of the student test scores,as an explanatory variable to the adult test score regressionswhere…. is mean years of schooling, all indexed by cohort c and country i, ensuring that the MYS data matches the same cohort for which the adult test scores are available. An increase in the years spent in the education system boost adult test scores in a statistically significant manner (Table 4, equations and ),although contrary to student test scores, the positive effect of mean years of schooling on adult test scores does not decline for older cohorts. The elasticity of cohort-specific adult skills with respect to student test scores is three to four times higher than the elasticity with respect to mean years of schooling.This result can be contrasted with the measures of learning adjusted years of schooling, which have been used in the literature but by construction usually impose the same elasticity for the quantity and quality components. Furthermore, this result can be used to combine the quality and quantity measures of education in a single stock measure of human capital…”…”