The standard version of q theory, in which investment is positively related to marginal q, breaks down in the presence of fixed costs of adjustment. With fixed costs, investment is a non-monotonic function of q. Therefore its inverse, which is the traditional investment function, does not exist....

The standard version of q theory, in which investment is positively related to marginal q, breaks down in the presence of fixed costs of adjustment. With fixed costs, investment is a non-monotonic function of q. Therefore its inverse, which is the traditional investment function, does not exist....