Mathematical Methods
in Economics
Dr. Vinci Chow
vincichow@cuhk.edu.hk
I
Dr. Vinci Chow and His Elite Team
• My office hour:
https://www.econ.cuhk.edu.hk/booked/Web/sc
hedule.php?sid=2
• Teaching Assistants:
• Max Hong
maxkhhong@cuhk.edu.hk
• Stephanie Hou stephaine@link.cuhk.edu.hk
• Jason Poon
1155143784@link.cuhk.edu.hk
Course Structure
• Weekly lectures
• Attendance not mandatory
• Lecture recordings in Cantonese and English will
be available after class each week
• (Almost) weekly assignments
• One final exam
Online Resources
• Blackboard:
https://blackboard.cuhk.edu.hk
Textbooks
Tutorial Time Slot Survey
http://bit.ly/45AKgt2
Source: whatonearthcatalog.com
©xkcd
ECONOMICS
Mathematical Economics
= Using mathematics to represent economic
models
Hate even more
Econometrics
= Statistical theory and
data analysis
Hate
Why Math?
✓Clarity
✓Generalizability
✓It also looks cool
Learning Outcomes
Source: funnyjunk.com
Learning Outcomes
✓ Familiar with basic mathematical tools
such as matrix and differentiation
Essssential to survival in the next 4 years
✓ Able to use computer programs to aid
their analysis
Useful for work
Python
• Python is an open-source, cross-platform
programming language
• Very intuition syntax, lots of extensions
Quick Guide to
Mathematical Symbols
Constant
Body weight = 50 + 5 × Ice−cream
Variable
Coefficient
Variable
These often need
to be solved
Quick Guide to
Mathematical Symbols
Parameter
Coefficient
𝑦 = 𝑎 + 𝑏𝑥
Variable
Variable
o Variables are usually represented with 𝑥, 𝑦 and 𝑧
o Parameters and Coefficients are usually represented
by 𝑎, 𝑏, 𝑐, …
Types of Numbers
-1, 0, 1, 2, 3,…
Integers
2
3
13 689
27 2017
Fractions
Rational Numbers
= any number that be expressed as
a fraction of integers
e.g. 2 = 2 / 1 so it is a fraction of integers
Types of Numbers
Irrational Numbers
= any number that cannot be
expressed as a fraction of integers
Types of Numbers
Rational Numbers
+ Irrational Numbers
= Real Numbers
Question to ponder:
What are fake
numbers?
ℝ
Source: scimathmn.org
Summation
෍
• The summation sign means summing up all
the elements:
10
෍ 𝑎𝑖 = 𝑎1 + 𝑎2 + ⋯ + 𝑎10
𝑖=1
Product
• The product sign means multiplying all the
elements:
10
ෑ 𝑎𝑖 = 𝑎1 × 𝑎2 × ⋯ × 𝑎10
𝑖=1