Lecture 1: Introduction to econometrics BUEC 333 Professor David Jacks 1 Start with a definition: the application of economic intuition/theory and statistical methods to analyze economic data. Emphasis of most courses in economics on theory (and maybe a little intuition); in this course, we focus on statistical methods. In particular, their application to real-world data problems encountered in academic, industry, and policy settings. What exactly is econometrics? 2 Need to recognize that econometrics is both a science and an art. Economic theory and statistics are grounded in mathematics—the “scientific” side. But there is always a disconnect between economic theory and the real world. Data is more often than not messy and requires finesse—the “artistic” side along with intuition. What exactly is econometrics? 3 Generally, we are interested in measuring or estimating particular economic relationships. From ECON 101, what is the price elasticity of demand for LED TVs? Manufacturers and retailers wants to know this variable when setting their prices. This could be—and is—estimated using econometrics and retail data; the rise of Amazon. Empirical questions demand empirical answers 4 From labor economics, does reducing class size improve the quality of education? Smaller classes = more attention = more learnin’ But how much more and is it worth it? Exploit variation in test scores and class sizes. Complications: what do scores truly measure? And does class size cause higher test scores or just correlated with some other variable? Empirical questions demand empirical answers 5 From finance, what will be the value of the S&P/ TSX index one quarter from today? Knowing with certainty worth a lot of money. But even knowing with some uncertainty is also valuable to portfolio managers. A pure forecasting problem: estimate the future value of the index based on its historical behavior and relation to economic fundamentals. Empirical questions demand empirical answers 6 The purpose of this class is for you to learn the statistical methods you would use to answer these questions…and many, many more. You will also learn how to assess whether a particular estimate/analysis is any good. You will learn to use a specific statistical software package (Stata) and get some experience with real data. What you will (hopefully) learn in BUEC 333 7 Academically, it is useful for future studies here at SFU (4th year courses) and grad school. Professionally, the past 10 years have seen a massive increase in data collection in industry; Big Data: source of FB/LI’s $300 b. valuation. Using that data will be a growth industry for the next ten years; New York Times, “For Today’s Graduate, Just One Word: Statistics”. Why should you care? 8 Even if doing something completely different, it is essential for understanding the broader world. This course will help you understand where estimates come from, how reliable they are, and what they do and do not actually mean… a valuable BS detector. This type of information should then guide your decisions as an individual consumer, investor, manager, voter… Why should you care? 9 But we must begin with a review of statistics. Things you hopefully learned in BUEC 232, but probably forgot in the meantime: 1.) random variables 2.) probabilities 3.) probability distributions 4.) expected values 5.) variances Next steps forward 10