::  Posts  ::  RSS  ::  ◂◂RSS  ::  Contact

Stock Delta as a Medium?

June 19th, 2012
probability  [html]
June 4th was the 24th anniversary of the 1989 Chinese crackdown on the Tiananmen Square protests. The Chinese stock market fell 64.89 points (6/4/89), making a lot of work for the censors. What I'm curious about, however, is how likely this was intentional.

On it's face this sounds unlikely enough to be intentional, but how unlikely is it? Over the last 200 days, Google Finance says the minimum has been -91.85 while the maximum has been 73.68. Naively taking these to be the bounds of possibility and assuming a uniform distribution (good enough for estimating) we get odds of 1 in 16553 of getting -64.89.

This isn't the only outcome that would look like June 4th 1989, however. There's also 64.89, ±46.89, ±89.46, and ±89.64. Having eight special numbers increases our odds by a factor of eight: 1 in 2069. Then there are two other Chinese stock markets, bringing our odds to 1 in 690. The stock market has been running for 21 june 4ths, any of which could have done this, bringing the odds down to 1 in 33.

When we consider how many other significant numbers there are in daily life, any of which could have come out to something readable as June 4th 1989, and especially when we add in the cost of manipulating this large a market, it sounds like this was a coincidence.

Comment via: google plus, facebook

Recent posts on blogs I like:

Maybe it’s not me– it’s grad school

Just a low effort post. I would love a mutually supportive comment discussion about it (because I’m not on facebook). Twitter replies would be nice, too.  I appreciated this post from Ben Kuhn, Grad school is worse for public health than STDs. In it he ca…

via Holly Elmore December 11, 2019

Grad school is worse for public health than STDs

(The way you can *really* tell something is horribly wrong is that grad students find PhD Comics darkly funny, not just dark.)

via benkuhn.net December 8, 2019

I’m Giving a Talk About Construction Costs Tomorrow

By popular demand, I’m giving the talk I gave 2 weeks ago at NYU, again. The database will be revised slightly to include more examples (like Ukraine, which I added between when I gave the talk and when I blogged about it), and I may switch around a few t…

via Pedestrian Observations December 2, 2019

more     (via openring)

More Posts:


  ::  Posts  ::  RSS  ::  ◂◂RSS  ::  Contact