The first of a two-volume set of articles reflecting the current state of research in econometrics.This is the first of a two volume set of articles reflecting the current state of research in theoretical and applied econometrics. The topics covered include time series methods, semiparametric methods, seasonality, financial economics, model solution techniques, economic development, and labour economics. All the contributions were commissioned to be presented at the plenary sessions of the Sixth World Congress of the Econometric Society in Barcelona.This is the first of a two volume set of articles reflecting the current state of research in theoretical and applied econometrics. The topics covered include time series methods, semiparametric methods, seasonality, financial economics, model solution techniques, economic development, and labour economics. All the contributions were commissioned to be presented at the plenary sessions of the Sixth World Congress of the Econometric Society in Barcelona.The topics covered in this volume include time series methods, semiparametric methods, seasonality, financial economics, model solution techniques, economic development, and labor economics. All the contributions were commissioned to be presented at the plenary sessions of the Sixth World Congress of the Econometric Society in Barcelona.1. Testing for the stationarity and the stability of equilibrium Mototsugu Fukushige, Michio Hatanaka, and Yasuji Koto; 2. Time series with strong dependence P. M. Robinson; 3. Recursive linear models of dynamic economies Lars Peter Hansen and Thomas J. Sargent; 4. The selection problem Charles F. Manski; 5. Quantile regression, censoring, and the structure of wages Gary Chamberlain; 6. The economics of seasonal cycles Jeffrey A. Miron; Comment Svend Hylleberg; 7. On the economics and econometrics of seasonality Eric Ghysels; Comment Denise Osborn. Written by the world's leading specialists, these papers are uniquely positioned to become aulĂ,