This paper discusses the issue of precondition for the number of researchers as an important input factor for research and development (hereinafter 'R&D'). R&D is one of the main sources for new knowledge creation through human capital. It can be seen as one of the most important sources of competitiveness.There was an analysis carried out on higher education graduates, who can be considered a base of a group of researchers, and the number of inhabitants. A method such as regression analysis for empirical data variables dependence was used. An assessment of quantitative indicators related to the number of inhabitants and the number of higher education graduates was performed by regression analysis. An analysis on higher education graduates and the number of inhabitants was conducted with the same method.These variables were examined for the European Union, the USA and the Czech Republic in the first decade of the 21st century. Based on the analysis values of all variables, a comparison of the countries was carried out.