section_path: Measuring and modeling the information revolution
section_name: Measuring and modeling the information revolution
paragraph_text: Measuring and modeling the information revolution
  
  Porat (1976) measured the information sector in the US using the input-output analysis; OECD has included statistics on the information sector in the economic reports of its member countries. Veneris (1984, 1990) explored the theoretical, economic and regional aspects of the informational revolution and developed a systems dynamics simulation computer model.
  
  These works can be seen as following the path originated with the work of Fritz Machlup who in his (1962) book "The Production and Distribution of Knowledge in the United States", claimed that the "knowledge industry represented 29% of the US gross national product", which he saw as evidence that the Information Age had begun. He defines knowledge as a commodity and attempts to measure the magnitude of the production and distribution of this commodity within a modern economy. Machlup divided information use into three classes: instrumental, intellectual, and pastime knowledge. He identified also five types of knowledge: practical knowledge; intellectual knowledge, that is, general culture and the satisfying of intellectual curiosity; pastime knowledge, that is, knowledge satisfying non-intellectual curiosity or the desire for light entertainment and emotional stimulation; spiritual or religious knowledge; unwanted knowledge, accidentally acquired and aimlessly retained.
  
  More recent estimates have reached the following results: