Temporal evolution of the technological impact of Mexican patents: An application of the expectation-maximization algorithm

  • Aurora A. Ramírez Álvarez El Colegio de México A.C.
  • Diana Terrazas Santamaría El Colegio de México A.C.
Keywords: patents, technological impact, networks, expectation-maximization algorithm, innovation
JEL Classification: O31, O33, D89


In this paper, we use the methodology of Clarkson et al. (2007) to analyze the patterns of citations of Mexican patents registered during 1968-2017 in the United States. Using an expectation-maximization algorithm and patent citations as an indicator of their utility, we find three groups of different citation pattern profiles: "Fast" receives the highest number of citations at a very early stage of their life (5 years), compared to "Medium" (10) and "Slow" (20). Moreover, the group "Fast" is associated with the most recent patents, with the lowest proportion of Mexican owners and inventors, and the highest economic value.


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How to Cite
Ramírez ÁlvarezA., & Terrazas SantamaríaD. (2020). Temporal evolution of the technological impact of Mexican patents: An application of the expectation-maximization algorithm. Estudios Económicos, 35(1), 37-69. https://doi.org/10.24201/ee.v35i1.397
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