抄録
Research, manufacturing, and sales as stages of innovation are inter-connected through 'knowledge". The source of corporate growth is indeed 'knowledge', that is created and maintained during innovation processes. Based on this idea, the author suggests indicators of R&D efficiency. The first index (called "Research Efficiency") is the ratio of technological progress to R&D investment. This index measures of the efficiency of an R&D division. The second index is the ratio of profit to technological progress. This index measures the efficiency of manufacturing and sales divisions. Total efficiency (ratio of profit to R&D investment) is equivalent to the first index by the second index. That is 'knowledge' as interface among stages of innovation, is explicitly treated in this index system. Finally, the author measures technological progress as the number of awarded research themes. This index of technological progress is expressed as a function of the period needed to complete it. That is, technological progress = αt exp (-βt^2). This equation was acquired by approximation in the case of Toyota Central Research Laboratory. From this equation, the period for producing maximum efficiency is (t_0+1√2β)[t_0: lead time]. So, we can say, we need to reconsider research projects that continue more than (t_0+1√2β) years.
