There is a mathematical way to tell net effect

It may be possible, however, to change the regulatory environment in ways which allow a higher sustained catch, and possibly with a lower level of expenditure on fishing. Let us denote the set of fishing regulations by ζ.  There are some regulations which allow fish to be caught without as large an adverse effect on the growth of the fishing stock, e.g. regulations that ensure that small fish are not caught.  We now write (4) dP/dt = H(P) – Q (P,n, ζ)M(ζ)  with M’ < 0. In other words, tighter regulations mean that the adverse effect of a given level of fishing is reduced, but Q 3 < 0, tighter regulations increase costs, and hence, at fixed P and n, lead to less fishing and a smaller catch.  It follows that with tighter regulation, the equilibrium level of P, denoted P2”, is increased. But that means that the flow of fish, H, has increased: tighter fishing regulations (in the sense defined) leads to an increased flow of fish, and this is true whether there is more or less investment in the fishing fleet. (That is, other things being equal, the increase in P results in a larger fishing fleet; but the increase in regulations leads to reduced investments, so the net effect is ambiguous.)(Figure 7) What is striking about these results, as we have noted, is that they reverse normal presumptions. Usually, general equilibrium responses diminish the magnitude of partial equilibrium responses, but do not reverse the sign.  Here (and in the analysis of the knowledge pool below) they do.    In the next section, we show that the same logic holds for innovation.    Changes in the environment which lead to more investment given a level of P, the size of the “knowledge pool,” may so diminish the equilibrium pool of knowledge (the set of technological opportunities) that the flow of innovations is reduced. This is true whether or not at the new equilibrium level of P, there is more or less investment in R & D.