We estimate investment policy functions under general assumptions about technology and markets. Policy functions are easy to estimate and summarize the key predictions of any dynamic investment model. Because our method does not rely on Tobin's Q, it does not require information about market...

We estimate investment policy functions under general assumptions about technology and markets. Policy functions are easy to estimate and summarize the key predictions of any dynamic investment model. Because our method does not rely on Tobin's Q, it does not require information about market...

This paper extends the Q-theory of investment to capital goods with arbitrary efficiency profiles. Under the assumption of geometric economic depreciation employed by the traditional Q-theory, a firm's replacement cost of assets-in-place is independent of their vintage composition and can be...