Lecture 1
Introduction to Econometrics
variable, omitted variable, population, sample, cross-sectional data, time-series data, panel data, descriptive question, causal question, reverse causality, statistical inference
Welcome to ECON 3300! This is the unofficial course website. It hosts the course lecture notes, Stata tutorials, and problem set solutions.
The official course website is on Brightspace, where you can find the syllabus,
weekly quiz solutions, exam materials, and your grades. I will also use Brightspace to
communicate with you through your
@lion.lmu.edu
email account, so please check your LMU email regularly. The subject line of all
course emails from me will begin with “ECON 3300.”
ECON 3300 is a foundational course for LMU Economics students. You will learn the fundamentals of regression analysis, tools that you will use throughout upper-level economics courses and that also underpin much of the political, policy, and business discourse you encounter outside the classroom.
If you master these tools, you will be better equipped to evaluate empirical arguments and, in particular, claims about whether a policy or intervention causes a particular outcome.
Suppose, for example, that a government official claims that more education increases future earnings in the United States. They point to data showing that people with more education tend to earn more on average. How should we evaluate the claim that education causes higher earnings? What must we assume about the data for us to believe that conclusion? And how confident should we be that the same relationship would appear in another data set?
These are the kinds of questions we will learn to answer in ECON 3300.
I have a few thoughts about how to succeed in this course, including how to study effectively and why I am asking you not to use AI when studying for this course. I’d like to share them with you here.
You should expect to spend roughly eight hours per week studying for ECON 3300 outside of class. I have designed the course with that expectation in mind. I recommend allocating those eight hours roughly as follows:
If you follow this routine consistently, you will be doing your part to get the most out of the course. I will do my best to make sure that this effort is rewarded with a deep understanding of the material and that your grade is a fair reflection of what you have learned.
The use of AI is prohibited in this course.
I prohibit AI use in this course for three main reasons.
AI is absolutely becoming an integral part of professional work. But the most common way people interact with AI today, through chatbots such as ChatGPT, is already quite easy to use, and it will only become easier. There are more advanced ways of using AI to write statistical code or develop software, but even these can be learned relatively quickly.
As AI becomes more ubiquitous, the ability to use it will become less scarce. As we know from ECON 1050, when the supply of a skill increases, the price employers are willing to pay for that skill tends to fall! By the time you graduate, employers may simply expect you to know how to use AI. What will remain more valuable is the knowledge and judgment that allow you to use AI effectively.
Econometrics will remain valuable because it teaches you how to interpret data, evaluate empirical claims, and recognize when an analysis is misleading. Developing this knowledge is difficult, and it is difficult to outsource. My goal in this course is therefore to help you develop the econometric understanding that will make AI more useful to you later, rather than use AI as a substitute for developing that understanding now.
Absolutely not. Although I typically grade on a curve, I have structured the course so that your grades reward a deep understanding of the material rather than your ability to produce work that you do not understand.
While AI use is prohibited, I cannot effectively enforce that rule on problem sets. For that reason, problem sets are graded primarily for effort, and you are rewarded for completing them successfully only to the extent that you also perform well on the corresponding in-class quiz. See the syllabus for the formal grading scheme.
The class project is also designed so that your grade reflects how well you understand your own work. A large share of the project grade comes from your presentation, where I will ask you questions about your analysis and your understanding of the project. The remainder of the course grade comes from the in-class midterm and final exam.
In short, not using AI will not put you at a disadvantage. If anything, using AI in place of working through the material yourself is likely to hurt your grade by weakening the understanding that the course is designed to assess.
AI can be detrimental to learning, but it can also be very useful for completing tasks when you already have the knowledge needed to critically evaluate its output. I use AI regularly to help me write code for interactive plots, simulate data, proofread lecture notes, produce early drafts of course materials, and think through econometric questions. That use extends to the materials for this course.
My promise to you is that I will never give you AI-generated material that I have not carefully reviewed and revised myself. I read every word to ensure that it is accurate, appropriate for the course, and consistent with what we discuss in class. The first drafts of many lecture notebooks on this website were developed with assistance from AI, but I then spent several hours revising each one so that the final version reflects exactly what I believe you should learn in this course.
I will never use AI to grade or evaluate your work.
You will receive feedback throughout the course in several ways.
Most Tuesdays, you will complete a 15-minute quiz covering material from the previous week. I will return your graded quiz in Thursday’s class and review the solutions with the class, giving you an opportunity to ask questions about anything you found confusing.
I will not return your problem sets, but I will post complete solutions on both this website and on Brightspace. Please review these carefully, especially for any questions you found confusing. For the class project, I will provide each group with verbal feedback following the presentation and a detailed written assessment on Brightspace.
I will post solutions to the midterm and final exam on Brightspace. You are welcome to review your graded midterm with me during office hours.
You are also always welcome to discuss your progress in the course with me during office hours or after class.
Specifically, by the end of this course, you will be able to
I hold office hours twice a week. You are welcome at either; no appointment is needed on Mondays, while Friday slots are one-on-one and reserved in advance.
Our peer mentor is an economics student who has done well in this course and can help you with the material, problem sets, and Stata.
If you are an educator interested in creating interactive course lecture notes like those on this website, please feel free to reach out. I’d be happy to share the underlying repository or offer guidance on creating your own materials, with appropriate attribution. You can contact me at robert.french@lmu.edu.