This book is intended for students having no knowledge in econometrics and little knowledge in statistics and in probability.
For a long time, the tradition in most countries was to teach econometrics the hard way. In a first stage, students had to learn plenty of mathematical results on various classes of estimators and tests. During this time they had to believe that their arid investment will be profitable in the future and will allow them to deal with economic data and to answer economic problems. Later on they could turn to applications.
A problem with this method is that many students became discouraged during the first step of the process. Another problem was that many students who had reached the second step had a tendency to turn to very sophisticated and fragile methods when they faced simple practical problems. Sometimes, the results they reached were crazy when they mixed very complicated methods, with very elementary mistakes contradicting basic common sense. The most serious mistakes in econometrics, which can even be found in articles published by good journals, come from not spending time enough looking at the data, in a pragmatic way, without a priori and without the strong desire to apply complicated methods that are totally inappropriate for these data.
