An in-depth empirical analysis of patent citation counts using zero-inflated count data model: The case of KIST

Abstract

Patent citation counts represent an aspect of patent quality and knowledge flow. Especially, citation data of US patents contain most valuable pieces of the information among other patents. This paper identifies the factors affecting patent citation counts using US patents belonging to Korea Institute of Science and Technology (KIST). For patent citation count model, zero-inflated models are announced to handle the excess zero data. For explanatory factors, research team characteristics, invention-specific characteristics, and geographical domain related characteristics are suggested. As results, the size of invention and the degree of dependence upon Japanese technological domain significantly affect patent citation counts of KIST.

Measuring technological distance for patent mapping

“…Forward citation count of a patent has been found to be an effective indicator of the economic impact of the patent in a number of prior studies (Albert et al, 1991;Hall et al, 2005;Harhoff et al, 1999;Lee et al, 2007;Trajtenberg, 1990 Table 5. Among all 12 networks, the one using normalized co-reference (A1) yields the highest correlations of vertices between their network centralities and total patent counts as well as forward citation counts.…”

The impact of convergence between science and technology on innovation

“…The results of the Vuong statistic test indicate that a zero-inflated negative binomial model shows a higher goodness of fit than a negative binomial model. Previous research had analyzed the citation variable of patent data using a zero inflated negative binomial model (Lee et al 2007), and in this research we also decided on using a zero inflated negative binomial model to test our hypotheses. Table 1 shows the descriptive statistics and correlations between the variables.…”

The Effects of Gender on the Quality of University Patents and Public Research Centres in Andalusia: is it Better with a Female Presence?

“…This variable is analysed by Tong & Frame (1994), as well as by Lee et al (2007), finding a positive relation with the value of the patent. In order to construct the variable, we have only taken into account those claims from each SAR with neither type X influences (which affect the originality of the patent and which would indicate that an invention equal to that requested has been found) nor any type Y influences (which affect the capacity for invention and which indicates that, by combining other documents cited in the report, it would have been possible to resolve the problem suggested).This differentiation is used by Schmoch (1993), who considers that this type of influence limits the claims made by the inventor in the patent, while Sampat & Ziedonis (2005) affirm that, when the content of the patent is included in the patent literature or in other foreign patents, the quality of the patent is inferior.…”