This paper is concerned with empirical and theoretical basis of the Efficient Market Hypothesis (EMH). The paper begins with an overview of the statistical properties of asset returns at different frequencies (daily, weekly and monthly), and considers the evidence on return predictability, risk...

How does factor accumulation affect the pattern of international specialization and returns to capital? We provide a new integrated treatment to this question using a panel of 44 developing and developed countries over the period 1976-2000. We confirm the Heckscher-Ohlin prediction that, with...

The current economic crisis requires fast information to predict economic behavior early, which is difficult at times of structural changes. This paper suggests an innovative new method of using data on internet activity for that purpose. It demonstrates strong correlations between keyword...

Credence goods markets are characterized by pronounced informational asymmetries between consumers and expert sellers. As a consequence, consumers are often exploited and market efficiency is threatened. However, in the digital age, it has become easy and cheap for consumers to self-diagnose...

We develop a theoretical model in which technology adoption decisions are based on the information received from others about the quality of a new technology and on their risk attitudes. We test the predictions of this model using a randomized field experiment in Bangladesh. We show that the...

Human communication in organizations often involves a large amount of gossiping about others. Here we study in an experiment whether gossip affects the efficiency of human interactions. We let subjects play a trust game. Third parties observe a trustee's behavior and can gossip about it by...

The central vs. local nature of high-school exit exam systems can have important repercussions on the labor market. By increasing the informational content of grades, central exams may improve the sorting of students by productivity. To test this, we exploit the unique German setting where...

We present a theorem helpful in estimating the mean and variance of a linear function with arbitrary multivariate randomness in its coefficients and variables. We derive a generalized decomposition result from two random linear functions in which the result can be applied to most models using...