Without certainty about government policies, business decision makers are unable to assess risk and opportunity and make the trade-offs necessary for investment in new technologies. Different policies (R&D, health and safety, economic regulation) have different effects, depending on type of industry and size of firm. Because there are no established standards for judging industry performance, it is difficult to know whether policy uncertainty is simply a rationalization for not innovating or whether there is a cause-and-effect relationship between policy uncertainty and technological change.