Our intuitions often leads us astray. A good reminder: study counterintuitive math and economic results.

Here are 9 of them 🧵

The Birthday Paradox

In a room of 23 people, there's a >50% chance that 2 people share the same birthday.

This type of probabilistic thinking does *not* come naturally to many people.
The Coastline Paradox

Fractal geometry is also confounding:

The coastline of a landmass does not have a well-defined measurement. As the unit of measurement gets smaller (eg. from KMs to cm), the length increases without limit.
Winner's Curse

In an auction, the winning bid will usually exceed the intrinsic worth of an item leading to a significant overpay (and negative net profit for the winner).
Braess's Paradox

Removing an extra road can make everyone's commute time faster.

Why? The existence of a "fast" road leads to congestion because everyone uses it. If you remove the shortcut, traffic flows better.
Market for Lemons

If a seller has slightly more info than a buyer (eg used cars), it can lead to market failure:

◻️Buyer will pay price below market (b/c they can't confirm quality)
◻️High-quality sellers leave market b/c can't get good price
◻️Only low-quality sellers remain
The Potato Paradox

If you take 100lbs of potatoes which are 99% water by weight and you let it dry so that they are 98% water, their new weight is 50lbs.
The Pizza Paradox

One 18-inch pizza has more "pizza" than two 12-inch pizzas (still trying to process this fact).
Littlewood's Law of Miracles

An example of the law of large numbers: A person can expect to experience events with odds of one in a million at the rate of about once per month.

(Similarly: in a world with ~8B people, a one-in-billion event will happen 8x a month)
Queuing Paradox

If bank customers take on average 10 minutes to serve and they arrive randomly at a rate of 5.8 per hour...then the waiting time for

◻️one teller is *5 hours*
◻️two tellers is *3 minutes*

Waiting time is reduced by 93x by adding a second teller.
PS. I write interesting threads like this 1-2x a week. Follow @TrungTPhan to catch them in your feed.

Also check out my weekly Saturday newsletter:https://t.co/jGZs8brnVR
Sources

Here's the breakdown of the queueing theory: https://t.co/2vunn5mMTz

Check this awesome article for dozens more counterintuitive math, science + physics facts: https://t.co/8sejjm6AkH
VERY counterintuitive fact: Gabriel's Horn is a geometric figure with:

◻️ *infinite* surface area
◻️ *finite* volume
Deep dive on the Birthday Paradox https://t.co/3AAXUUVGP9

More from Trung Phan 🇨🇦

More from Finance

If you want to become financially independent and don't know where to start, here is a thread that will help you get started

/THREAD/

1. Review your expenses and make a budget

It will help you see where you overspend, make a plan to save, pay down debt and start


2. Set your investing and retirement goals

How much do you need to support yourself in retirement and when do you want to


3. The earlier you start investing, the better.

Here's why and how time and compounding can become your


4. Invest in an index fund

It's easy, safe, cheap, and the best choice for a beginner in investing, with not much time for

You May Also Like