The Q-theory of investment says that a firm's investment rate should rise with its Q. We argue here that this theory also explains why some firms buy other firms. We find that 1. A firm's merger and acquisition (Mamp;A) investment responds to its Q more -- by a factor of 2.6 -- than its direct...

We study 114 years of U.S. stock market data and find That there are large cohort effects in stock prices, effects that we label 'organization capital,' That cohort effects grew at a rate of 1.75% per year, That the debt-equity ratio of all vintages declined, That three big technological waves...

We study the relation between IPO investment and the rate of interest. We model the IPO timing decision and show that the implied relation between interest rates and investment is non-monotonic, and the data support the implication. At low rates of interest firms delay their IPOs. This happens...

Our paper reports the following two findings: 1) In monthly data, bond purchases by the Fed raise bond prices and reduce bond yields. The residual bond-supply to traders is not fully predictable, and this supply-risk adds between 10 and 40 basis points to the standard deviation of the real...

We find that new firms real investment responds much more elastically to aggregate Tobin s Q than does that of established firms. On the financial side, IPOs respond more elastically to Tobin s Q than seasoned offerings of securities. The explanation seems to be that a high aggregate Q raises...

Electricity and Information Technology (IT) are perhaps the two most important general purpose technologies (GPTs) to date. We analyze how the U.S. economy reacted to them. The Electricity and IT eras are similar, but also differ in several important ways. Electrification was more broadly...

Firms that entered the stock market in the 1990s were younger than any earlier cohort since World War I. Surprisingly, however, firms that IPO'd at the close of the 19th century were just as young as the companies that are entering today. We argue here that the electrification-era and the IT-era...

Growth of technological variety offers more scope for the division of labor. And when a division of labor requires some specific training, the technological specificity of human capital grows and, with it, probably the firm specificity of that capital. We build a simple model that captures this...

We argue that takeovers have played a major role in speeding up the diffusion of new technology. The role that they play is similar to that of entry and exit of firms. We focus on and compare two periods: 1890-1930 during which electricity and the internal combustion engine spread through the...

We study private equity in a dynamic general equilibrium model and ask two questions: (i) Why does the investment of venture funds respond more strongly to the business cycle than that of buyout funds? (ii) Why are venture funds returns higher than those of buyout? On (i), venture brings in new...