This paper proposes a search strategy for photovoltaic patents which allows to distinguish the photovoltaic system into sub-trajectories. Identifying and analyzing sub-trajectories is of particular importance for understanding micro patterns of technological change. The proposed search strategy...

We present a selective survey of the economic theory of intellectual property rights. After a brief description of the institutional framework, we discuss policy objectives and some basic welfare tradeoffs in intellectual property design. We consider the extent to which social objectives can be...