In this survey, I discuss four sources of growth of knowledge: research, schooling, learning by doing, and training. In trying to disentangle what is important, I emphasize the following facts: (1) even the most advanced countries spend far more on adoption of existing technologies than on...

We model research as a signal on an unknown parameter of a technology. We distinguish applied from basic research and show that firms in the same industry can optimally choose different research portfolios, and that basic research can seem to have a higher rate of return than applied research,...

We survey the recent literature on learning in financial markets. Our main theme is that many financial market phenomena that appear puzzling at first sight are easier to understand once we recognize that parameters in financial models are uncertain and subject to learning. We discuss phenomena...

Investor sophistication has lagged behind the growing complexity of retail financial markets. To explore this, we develop a dynamic model to study the interaction between obfuscation and investor sophistication. Taking into account different learning mechanisms within the investor population, we...

In many industries firms can learn about new technologies from other adopters; mandatory disclosure regulations represent an understudied channel for this type of social learning. We study an environmentally-focused law in the shale gas industry to examine firms' claims that disclosure...

Relationship-specific learning is consequential because it implies that relationship stability is important to productivity. When two firms accumulate experience working together, relationship-specific intellectual capital is created that cannot be appropriated to pairings with other firms. If...

This paper is based on the premise that knowledge about the alphas of one set of funds will influence an investor's beliefs about other funds. This will be true insofar as an investor's expectation about the performance of a fund is partly a belief about the abilities of mutual fund managers as...

This article establishes four key findings of the growing literature on experience effects in finance: (1) the long-lasting imprint of past experiences on beliefs and risk taking, (2) recency effects, (3) the domain-specificity of experience effects, and (4) imperviousness to information that is...

We conduct a randomized experiment that generates exogenous variation in the access to foreign markets for rug producers in Egypt. Combined with detailed survey data, we causally identify the impact of exporting on firm performance. Treatment firms report 16-26 percent higher profits and exhibit...