Introduction Economics 302 - Microeconomic Theory II: Strategic Behavior Shih En Lu Simon Fraser University ECON 302 (SFU) Introduction 1 / 17 Welcome to ECON 302! Instructor: Shih En Lu Next hour: 1 2 Overview of the course material Functioning of the course ECON 302 (SFU) Introduction 2 / 17 When Markets Work Well In ECON 201, you focused on markets where: 1 2 3 there are many buyers and many sellers; everyone knows all the relevant information (e.g. characteristics of the good); and transactions do not directly impact third parties. As a result: 1 2 3 market participants take prices as given, and buy [sell] as long as their valuation of the good is higher [lower] than the price; these valuations accurately re‡ect the buyers’bene…t and the sellers’ cost; and these bene…ts and costs correspond to the bene…ts and costs for the overall economy. ECON 302 (SFU) Introduction 3 / 17 What Can Go Wrong? (I) Some markets fail to have many sellers. In this case, sellers realize that selling more leads to a lower price. So while selling an extra unit at P dollars still brings in P from the sale, it also costs the …rm through a lower price on all the units that would have been sold anyway. Marginal revenue is less than the price. The seller will therefore produce a quantity where its marginal cost is below the price =) ine¢ ciency! Similar problem arises when there are few buyers. ECON 302 (SFU) Introduction 4 / 17 What Can Go Wrong? (II) Sometimes, information about a good can be incomplete. This is especially problematic when one side of the market knows less than the other. An insurance company doesn’t know exactly how risky its customers are. So it can have a hardtime gauging the cost of the service it provides. Insured customers are tempted to act less carefully, and one cannot fully monitor their behaviour. These problems can preclude the e¢ cient outcome, and could even make the market unravel completely. ECON 302 (SFU) Introduction 5 / 17 What Can Go Wrong? (III) Finally, some transactions impact third parties. Much of this course deals with these market failures: 1 2 3 Market power: monopoly, oligopoly Asymmetric Information: hidden action (moral hazard), hidden characteristic (adverse selection) Externalities and public goods (brie‡y) ECON 302 (SFU) Introduction 6 / 17 Where Game Theory Comes In Under perfect competition, as long as you know the price, you can maximize utility/pro…t without worrying about other market participants’behaviour. When there are two or more …rms with market power, each …rm must anticipate other …rms’behaviour, which a¤ects the price. When there is hidden information, the uninformed party must take into account how the informed party will react to its decisions. How do we analyze these complex situations? Game theory: a toolbox for studying "strategic" behaviour. ECON 302 (SFU) Introduction 7 / 17 This Course My o¢ ce is WMC 4661. TA and our OHs: see syllabus. Come and see us during o¢ ce hours, or by appointment - don’t be shy, but be well prepared. Don’t come outside of o¢ ce hours unless you have an appointment. Textbooks: none required. See syllabus for recommendations. Slides will be posted before lecture. They are not su¢ cient on their own as notes: you should complete them with your own notes during class. ECON 302 (SFU) Introduction 8 / 17 Homework 9 problem sets. Discuss problems with each other - most of you will learn a lot from each other - but write your own solutions. Due at the beginning of lecture on dates indicated on the syllabus Can erase up to 25% of the marks you lose on exams - see course document for details Only graded for completeness - so don’t copy from others or last semester’s solutions Each problem set is worth 5 points, and you only need 39 points for the maximum grade bene…t. You will not be allowed to make up or receive an adjustment for the …rst problem set missed for a valid reason, since you can still get 39 points from the other 8. ECON 302 (SFU) Introduction 9 / 17 Exams A quiz (28 points), a midterm (72 points) and a …nal (125 points) Slightly shorter - so hopefully more manageable - than past years You must see me at least 7 days before the quiz/midterm for an exemption (except for medical emergencies). If you miss the quiz/midterm for a medical reason, you must present (email is …ne) an SFU Certi…cate of Illness within 10 days of the test. You must see the doctor on or before the day of the test. Email me this week if you will miss the …nal for religious reasons. Otherwise, only medical emergencies are acceptable. See the document posted online for detailed rules. ECON 302 (SFU) Introduction 10 / 17 What You’re Getting Yourself Into In high school, the teacher did problems in class. Then you repeated the same problems (with di¤erent numbers) on the homework. And then, you repeated the same problems again on the exam. This is an upper division university course, where you’re expected to think on your own. The lectures will teach the theory. Time permitting, we will go over basic examples. You will need to …gure out how to solve the problem set questions, some of which are complicated. Part of the exams will test whether you can apply course concepts to problems that you haven’t encountered before. ECON 302 (SFU) Introduction 11 / 17 What You’re Getting Yourself Into (II) If you expect to be spoon-fed problem-solving methods and get by using rote learning and "plug ’n chug," you will be frustrated and miserable. If you are ready to think deeply about the material and …gure out di¤erent ways to apply it, you will …nd this course rewarding, learn a lot and maybe even have fun along the way. I’ve posted some tips online from me and from former students. Go read them if you’re worried. This course is not taught at a graduate level, where one spends lots of time proving things mathematically. However, this course should provide good preparation for graduate coursework. ECON 302 (SFU) Introduction 12 / 17 What You’re Getting Yourself Into (III) I’m very blunt. If you’re wrong, I’ll say it directly. If you don’t know something basic that was repeatedly emphasized in class, I’ll tell you that’s not OK. Remember that I’m just being direct, and I’m not judging you as a person. I cold call, especially when there are no volunteers to answer a question. This is not to put people on the spot, but rather to get an idea of what people are struggling with. I don’t typically remember who I call upon, so don’t take it personally if I use your answer to illustrate common mistakes that people make. Ultimately, I want all of you to succeed (but I will not arti…cially make that happen by lowering standards). If I get frustrated, it’s usually not at you, but simply at the results. ECON 302 (SFU) Introduction 13 / 17 My Expectations Don’t try to leave class before time unless I’m done. Never fall behind. You should understand everything in a week’s lecture slides before the following week’s lectures. On average, each problem set should take you around 4-7 hours. This is entirely reasonable for a 4-credit course with no papers and no required readings. However, some of you will need more time (and others less). Everybody should aim to get full marks on problem sets. Learn the de…nitions. Because most exam questions are di¤erent from problem set questions, you will have trouble understanding them if you do not bother learning what the words mean. ECON 302 (SFU) Introduction 14 / 17 Grading There is no set pass mark due to variation in exam di¢ culty across semesters. There is no …xed grading scale. There is no set grade distribution due to variation in student quality across semesters. There is no …xed curve. In semesters where multiple sections of ECON 302 have similar student quality (as judged by their CGPA distribution), the instructors use similar grade distributions. Read the syllabus and course policies carefully and never ask for an exception: the answer is NO. Asking for an exception (for example, "Can you shift some weight from this exam to that exam?") will simply get you -1 on your …nal grade. ECON 302 (SFU) Introduction 15 / 17 Why Hard Exams Are Good For You They reward understanding rather than learning by heart. If you just learn the material by heart, you’d forget it a week after the …nal, and this whole course would be a huge waste of your time. Suppose you have a bad day on the midterm. If the …nal is easy, you can’t catch up! So hard exams make the course more forgiving. You’re sure that you won’t be "curved down": much better to get 45% and realize that’s a C than to get 60% and realize that’s a D! So don’t be demoralized by low numerical scores: if you can get over the "sticker shock", they’re actually good for you! ECON 302 (SFU) Introduction 16 / 17 Why This Course Is Very Quantitative (Much of) microeconomic theory = 1 2 express common sense hypotheses as precise mathematical assumptions, and then use math again to derive results from the assumptions and make sense of the world. Math helps identify hidden/implicit assumptions that might not always hold, and helps avoid con‡ating related but di¤erent concepts. We will use things you should have learned in ECON 103, ECON 201, MATH 157 and BUEC 232. ECON 302 (SFU) Introduction 17 / 17