UC Davis · ECN100B · Intermediate Micro Theory: Imperfect Competition & Market Failure

ECN100B: pass the exams, not just read the notes

Your complete guide to University of California, Davis's intermediate micro theory: imperfect competition & market failure course. See where the marks are, work real practice questions, and study with an AI tutor that knows ECN100B.

4 credit points core) undergrad Offered Fall / Winter / Spring ~70% exams Department of Economics

Sia generates ECN100B practice questions, works through them step by step, and quizzes you on the material the exam weights most heavily.

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Worked example

Multiple choice · solution revealed after you answer

In a one-shot prisoners' dilemma, each firm can 'cooperate' (keep prices high) or 'defect' (cut prices). Defecting yields a higher payoff regardless of what the rival does. What is the Nash equilibrium?

Worked solution

A Nash equilibrium is a set of strategies where no firm can do better by changing its own strategy, given the other's.

Here defecting yields a higher payoff regardless of the rival's choice — defect is a dominant strategy for each firm.
Since both firms have the same dominant strategy, both defect.
This is the classic prisoners' dilemma: the equilibrium (both defect) is worse for both than mutual cooperation, but cooperation is not individually stable in a one-shot game.

The trap: Assuming firms reach the jointly best outcome (both cooperate). In a one-shot prisoners' dilemma, defect is dominant, so the Nash equilibrium is mutual defection even though it is worse for both. classic slip!

your whole grade
Where your grade comes from Exams 70% · Assignment 25% · Participation 5%

One exam decides 40% of your grade. This whole page is built around that.

Overview

What ECN100B is, and where it sits

ECN 100B Intermediate Micro Theory: Imperfect Competition & Market Failure is an upper-division core course for the economics major at the University of California, Davis, taught in the Department of Economics on the quarter system. It is the second half of intermediate microeconomics: having covered competitive markets, it turns to imperfect competition (monopoly, oligopoly and monopolistic competition), strategic behaviour through game theory, and the ways markets fail — externalities, public goods, and asymmetric information — along with the welfare consequences and policy responses.

The course is calculus-based and analytical. The grade combines problem sets, a midterm and a final in the standard US pattern. The recurring skill is building and solving models of firm and strategic behaviour — optimisation, equilibrium, and welfare analysis — and using them to judge when and why markets fail and what policy might do about it.

How it differs from its first-year siblings. ECN 100B is the second-half intermediate-micro core: it moves from competitive markets to strategic firm behaviour and market failure, with calculus-based optimisation and game theory at its centre.

Difficulty & time commitment

Is ECN100B hard, and how much time does it take?

ECN100B is manageable if you keep a weekly rhythm and treat the back half as the main event. The pattern is consistent: it starts gently and steepens, and the heaviest assessment is the part that separates grades.

Difficulty
3.5 / 5
Moderate–Hard. Gentle early, demanding back half. Hard to fail with steady work; a top grade takes consistent practice.
Exam load
70%
The exams decide most of the grade. The heaviest single component is 40%.
Firm behaviour & market powerbuilds the toolkit
Game theory & market failuresteep

The difficulty curve and the assessment weighting point the same way: the back half is harder and worth more. Front-loading effort there is the highest-return decision in the course.

Is this course for you

Who tends to do well, and who tends to struggle

You will likely do well if

  • You are comfortable with calculus-based optimisation and algebra.
  • You practise setting up and solving games and market-failure models, not just reading them.
  • You can connect the models to welfare and policy conclusions.

You may struggle if

  • You are rusty on calculus and constrained optimisation.
  • You memorise results without being able to derive equilibria.
  • You fall behind through the steeper game-theory-and-market-failure half.
do this ↘
What top students do differently
  • Drill firm optimisation (MR = MC across market structures) and derive results, don't memorise them.
  • Practise finding Nash equilibria in payoff matrices and simple continuous games.
  • Build a market-failure sheet: each failure, why it happens, and the policy fix.

Syllabus

The 5 topics, topic by topic

The exam-weight marker on each topic shows where the marks concentrate. The amber topics carry the highest exam weight.

T1 · Monopoly and market power

Lower exam weight

T2 · Oligopoly and monopolistic competition

Lower exam weight

T3 · Game theory and strategic behaviour

Lower exam weight

T4 · Externalities and public goods

Lower exam weight

T5 · Asymmetric information and market failure

Lower exam weight

How it's assessed

Assessment structure

ComponentWeightFormat & timing
Final exam40%Comprehensive final. Finals week.
Midterm exam30%In-class midterm. Mid-term.
Problem sets25%Regular problem sets. Across term.
Participation5%Section participation. Across term.
Final exam40%
Comprehensive final.
Midterm exam30%
In-class midterm.
Problem sets25%
Regular problem sets.
Participation5%
Section participation.
  • Letter-graded; pass on the standard institutional scale. Assessment weights are indicative of the standard US structure for this course type — confirm the exact breakdown on your official course syllabus.
read this! If you read nothing else

This is an exam-cram course. With the exams at 70% of the grade and the final exam alone at 40%, your result is overwhelmingly decided by how well you perform under time pressure.

How to actually pass it

A weekly rhythm, two checklists, and the traps to avoid

The course rewards consistency over cramming, and practice over re-reading. Here is the loop that works, then what to have nailed before each exam.

The weekly loop

Each week
Work the problem set and derive each equilibrium and optimisation result by hand.
Per topic
Link the model to its welfare and policy implication.
Weekly
Maintain a market-structures-and-failures sheet you can reproduce.

Before the mid-semester checklist

Before the final heaviest topics

  • Master monopoly, oligopoly and monopolistic-competition pricing.
  • Drill game theory — dominant strategies and Nash equilibrium.
  • Revise externalities, public goods, asymmetric information and their welfare and policy analysis.
  • Practise full calculus-based problems to exam timing.

The mistakes that cost marks

01

Assuming cooperation in a dilemma. In a one-shot prisoners' dilemma the Nash equilibrium is mutual defection; expecting the jointly best outcome is the classic game-theory error.

02

Weak calculus base. Constrained optimisation underpins the firm and welfare analysis; a shaky base makes the models much harder.

03

Memorising over deriving. Exams reward deriving equilibria and welfare results, not reciting them.

Teaching team

Who teaches ECN100B

No teaching staff are publicly listed for this offering. Check the official course page for the current coordinator and lecturers.

Where it fits

Prerequisites, related courses & why it matters

Upper-division core course for the economics major at UC Davis; assumes intermediate-micro prerequisites and calculus. Check the official UC Davis Economics catalog for prerequisites.

Why it matters beyond the grade. Intermediate micro with game theory and market failure underpins later fields — industrial organisation, public economics, and the strategy and policy roles they lead to.

FAQ

Frequently asked questions

How is ECN 100B assessed at UC Davis?

As an upper-division core course on the quarter system, ECN 100B typically combines problem sets, a midterm and a final exam. The AskSia guide maps the models most likely to be tested and how to derive them. Exact weights vary by instructor and quarter — confirm on your official course syllabus.

What does ECN 100B cover?

The second half of intermediate microeconomics: imperfect competition (monopoly, oligopoly, monopolistic competition), game theory and strategic behaviour, and market failures (externalities, public goods, asymmetric information) with their welfare and policy analysis.

Is ECN 100B hard?

It is a moderate-to-hard core course because it is calculus-based and analytical — optimisation, game theory and welfare analysis. Students comfortable with calculus who practise deriving results generally find it manageable.

What is the difference between ECN 100A and 100B?

At UC Davis, intermediate microeconomics is split: 100A covers competitive markets and consumer/producer theory, while 100B covers imperfect competition, game theory and market failure. This guide is for 100B.

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