Thoughts on Probability and Statistics | The 2020 Novel Coronavirus Outbreak

The Wuhan coronavirus (2019-nCoV) is currently spreading throughout China and the world. As of Jan 25, 12am EST, there are 1,354 confirmed cases and 41 confirmed deaths throughout the world. …

Thoughts on Probability and Statistics

What is a black swan event, and where do they come from?

The idea of a black swan dates as far back as the time of the Roman poet Juvenal.

rara avis in terris nigroque simillima cygno — From The Satires, Line 6.165

Translation: A rare bird in these lands, very much like a black swan.

Historically, it was presumed that black…

Investing is a risky endeavour. Take a wrong step, and you could find your cash burned up. So how do you pick the right investments? Should you trust news? Should you trust the brokers? Should you do your own research? Or should you pay someone else to manage your investments?

Calculating a running average

In my last post on insurance, I wanted to calculate a running mean (the mean from the beginning up to the current time t). This was for a time series with 1,000,000 time-steps. In order words, I had to calculate 1,000,000 means. How did I do this?

Algorithm 1: straight out of a math (and not a CS) textbook

If you look…


Introduction — A simple model of savings
Part I — The benefits of an insurance scheme
Part II — The law of large numbers
Part III — When insurance schemes fail
Appendix — Math for the simulation

Inspired by Ole Peters (lecture) and Nassim Nicholas Taleb.

This article strings together…

Social Distancing: “Is this far enough, officer?”

Which genius decided on the rules for social distancing?

This is the official advice from the Australian government on public gatherings during this COVID-19 coronavirus outbreak.

Stay 1.5 metres away from others

I don’t know how long 1.5 metres is, and I don’t have a ruler on me. Neither do my neighbours, and who knows if…

The 2020 Novel Coronavirus Outbreak | Thoughts on Probability and Statistics

If you are reading this after 2020, please keep in mind that this post was written during the early stages of the COVID-19 pandemic, and hence, may not reflect a reality beyond this time.

We are currently in February 2020. Over the past month, a deadly virus has been spreading…

Thoughts on Probability and Statistics

How to Understand the Idea of “Average”

Formulas Are For Calculation, Not For Understanding

When people teach you about statistical concepts, you usually get a equation which is a formula for some quantity, like the arithmetic mean. Formulas are fine, but they are designed with calculation in mind. …

The 2020 Novel Coronavirus Outbreak

Update (Feb 10): Some researchers have estimated the case-fatality rate. In my new post, I summarize their research and explain why it’s worse than it looks.

At the start of 2020, murmurs of a mysterious SARS-like coronavirus started to spread in the city of Wuhan, in Hubei, China. Soon enough…

Andy Chen

Math, stats, data. Influenced by the complex systems perspective. I prefer to take the critical view.

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