Here at last is the fourth edition of the textbook that is required reading for economics students as well as those practising applied economics. Not only does it teach some of the basic econometric methods and the underlying assumptions behind them, but it also includes a simple and concise treatment of more advanced topics from spatial correlation to time series analysis. This book's strength lies in its ability to present complex material in a simple, yet rigorous manner. This superb fourth edition updates identification and estimation methods in the simultaneous equation model. It also reviews the problem of weak instrumental variables as well as updating panel data methods.