A mixed model of regression with error components is proposed as one of possible interest for combining cross section and time series data. For known variances, it is shown that Aitken estimators and covariance estimators are in one sense asymptotically equivalent, even though the Aitken...

Several recent papers argue that contracts provide reference points that affect ex post behavior. We test this hypothesis in a canonical buyer-seller relationship with renegotiation. Our paper provides causal experimental evidence that an initial contract has a highly significant and...

We present an international trade model with multiproduct firms. Firms are heterogeneously endowed with two types of capabilities that jointly determine the trade-off within firms between managing a large portfolio of products and producing at low marginal cost. The model can explain many of the...

This paper reports data from a laboratory experiment on two-period moral hazard problems. The findings corroborate the contract-theoretic insight that even though the periods are technologically unrelated, due to incentive considerations principals can benefit from offering long-term contracts...