On November 25th, Jack Dick-weed sold TWTR options for $4.8M

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.

The payments wars in Japan are heating up and one of the battlegrounds is convenience store coffee.

“Coffee? What does that have to do with payments?” I’m glad you asked.

Convenience stores are low net margin businesses, which sell some high gross margin goods/services but a lot of low ones, and have high fixed costs and a low ticket size. The typical transaction is under 500 yen ($5) and many are about $1.

They need repeat custom.

A few years ago, all of the chains had a good idea for increasing frequency of use: make a minor capital investment in automatic coffee machines. Sell access to them for the price of a cup / ice; customers self-serve with the machine.

The price point is $1 to about $2.

Coffee quickly became one of the most frequently repurchased items at convenience stores, in no small part because it’s the one thing they can sell which is phameceutically habit forming but totally unregulated. (Just telling it like it is.)

But the coffee is not very defensible

The problem, such that it is, is that competing chains are everywhere and *all* of them serve Thoroughly Adequate Coffee at similar prices, so you’re back into the brutal economics of “Who is 3 meters closer to 40 customers at 1 office?”

Enter payment apps.

The most memorable interview I did this year was w/ Stanley Druckenmiller, who famously made $1B shorting the British Pound.

The trading legend's track record includes a 30-year stretch returning 30%+ a year (without a single down year).

Here are 8 investing lessons🧵

1/ Make concentrated bets in high conviction plays

2/ Concentrated bets can sometimes *reduce* risk

3/ Use a multi-disciplinary approach to investing

4/ Know when to sell (he never uses a stop loss)

Way to #Financial freedom

1) Rule of 72 (Double Your Money)
2) Rule of 114 (Triple)
3) Rule of 144 (Quadruple)
4) Rule of 70 (Inflation)
5) 4% Withdrawal Rule
6) 100 - Minus Age Rule
7) 10, 5, 3 Rule
8) 50-30-20 Rule
9) 3X Emergency Rule
10) 40% EMI Rule
11) Life Insurance Rule

1) Rule of 72
No. of yrs required to double your money at a given rate, U just divide 72 by interest rate
Eg, if U want to know how long it will take to double your money at 8% interest, divide 72 by 8 and get 9 yrs

At 6% rate, it will take 12 yrs
At 9% rate, it will take 8 yrs

3) Rule of 144

No. of years required to, quadruple your money at a given rate, U just divide 144 by interest rate.

For eg, if U want to know how long it will take to quadruple your money at 12% interest, divide 144 by 12 and get 12 yrs

At a 6% interest rate, it will take 24yrs

4) Rule of 70

Divide 70 by the current inflation rate to know how fast the value of your investment will get reduced to half its present value.

The inflation rate of 7% will reduce the value of your money to half in 10 years.

5) 4% Rule for Financial Freedom

Corpus Reqd- 25*Annual Expenses

Eg- the annual expense is 500,000 then the corpus required to retire is 1.25 cr.

Put 50% into fixed income & 50% into equity.

Withdraw 4% every yr, i.e.5 lac.

This rule works for 96% of the time in 30 yr period