Public research and development refers to the R&D activities related to public sectors, including governments, colleges and non-profit organizations. Public R&D include academic fundamental research, applied research and R&D grants and contracts to private sectors, where later two are known as 'R&D subsidy'. Public R&D could be understood as a funder or a performer of an R&D activity. According to National Science Foundation in U.S., in 2015, R&D expenditures performed by federal governments, local governments, colleges and non-profit organizations are 54, 0.6, 64, and 20 billions of dollars, respectively. Meanwhile, industries perform R&D expenditures of 356 billion dollars. Moreover, R&D expenditures funded by federal governments, local governments, colleges and non-profit organizations are 121, 4.3, 17, and 19 billions of dollars, respectively. R&D expenditures funded by industries are 333 billion dollars. In terms of R&D funders, public R&D to private R&D ratio is about 0.5.