Resumen
Research question: This article considers the problems of measuring public sector innovation by asking the question whether and why interpretation of the achievements regarding the public sector innovativeness might be questionable. Motivation: The most recent literature on public sector innovation reveals two perspectives. One of them is assertion that the public sector suffers an innovation deficit, while the other claims that it is actually more innovative than a common credit. Insights in the results from recent large studies of measuring public sector innovation have shown very high rates of innovations, higher than in private sector (between 50 % and 80 % of respondents have recorded at least one type innovation during the period of two years). The lack of a uniquely, or at least dominant, attitude regarding the above-mentioned standpoints represents the basic inspiration for the actualization of this problem. Idea: The aim of the paper is twofold: 1) to offer an overview of three established theoretical attempts (assimilation, demarcation and integrative) dealing with public sector innovation, in order to present the evolution of the issue; 2) to prove that the inclination to more general over contextually specific understanding of innovation (and vice versa) has an impact both on its operationalization and on the interpretation of the achievements. Findings: In spite of the fact that theoretical considerations show noticeable detachment from assimilation perspective, empirical studies still copy this approach and the associated methodology. Surveys introduced subjectivity through arbitrary interpretation of the innovation concept, choice of research techniques and respondents and using of non-measurable goals as indicators of innovation outputs. Since this has affected and overrated their outcomes, we have found that empirical studies have not provided reliable depiction of the state of affairs regarding the PSI. Contribution: Having presented theoretical and methodological arguments why relying on the assimilation approach is neither the only nor even the most adequate way to answer the question whether the public sector is more innovative than the private one, we point to the necessity of using the other two approaches, particularly integrative one in order to find a coherent method of PSI measurement.