美国为研究与开发（RD）活动付出了很大努力。这些努力及其结果在经济增长和相关的许多方面（比如国家防御、产业竞争力、公共健康、环境质量和社会福利等）发挥着相关作用。然而，关于研究与开发活动的测度，尤其是在国民经济的整体框架里测度研究与开发活动对国民经济的能动 The United States has devoted a great deal of effort to research and development (RD) activities. These efforts and their consequences play a relevant role in economic growth and many related aspects such as national defense, industrial competitiveness, public health, environmental quality and social welfare. However, the measurement of research and development activities, especially the measurement of the ability of research and development activities to stimulate the national economy in the overall framework of the national economy