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Cryptic comment on A- vs. H-shares valuation gap

This Bloomberg article brings to our attention that

Shares in the yuan-denominated CSI 300 Index traded at 16.2 times earnings this month, compared with 8.6 times for 43 mainland companies in Hong Kong.

and that

The average gain in China is 23 percent this year, while the same companies are down 4.8 percent in Hong Kong, … China is among three of the four so-called BRICs economies where local shares are providing bigger returns than are available to foreigners … Russia’s Micex index, up 21 percent in rubles since Dec. 31, gained 2.5 percent when measured in dollars. A 9.2 percent decline in India’s Sensitive Index widens to 14 percent in dollars. The exception is Brazil, where the Bovespa Index has risen 5.7 percent, versus a 3.9 percent gain in reals.

The A-shares have always been overvalued compared to the H-shares, when measured against any benchmark currency and people have puzzled over this for a long time. The article itself offers two explanations
(Read the article)

on analogic reality

I was on UK’s Daily Mail newspaper web site and suddenly this thing caught my eye. It was a flash ad promoting the newspaper, a veritable montage of “interesting things” that, through implication, the newspaper reported on. This is very common on local TV stations, which promote themselves this way. Innocuous enough, except I thought … wait a minute, isn’t this the infamous Kingdome implosion?

Sure enough, it was, and you can see it on Youtube.

Some local Seattle event is a bit far from the UK, and sure enough the Daily Mail never reported on this back in the day so far as I can tell. A bit of artistic liberty, surely, but perhaps there is more to it.
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sleep … and a smart alarm

http://www.sleeptracker.com/sleep-images/sleeptracker-pro-big01.jpgIn honor of the stupidity that is Daylight Savings Time, I’ll write about sleep.

First, this watch seems pretty interesting. It is based on the idea that if you’re never going to get enough hours of sleep a night anyway, then you are best to get a full number of sleep cycles, rather than a fractional one. So it tracks your sleep cycle and wakes you up when you’re most awake.

This reminds me of my general annoyance with the whole concept of sleep and the inefficiency it causes. Sleep has got to be one of the worst vestigial devices still left in humans, although not as bad as the appendix.

Years ago, I came across a blog in which the person was trying out the concept of polyphasic sleep, which is basically napping frequently for short periods each time. The idea was to save total amount of time slept, I guess, or to make sleep more efficient. I guess it worked out well enough to cause a whole bunch of fanatical people to try it.
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Is this true?

So this thing on Wikipedia

http://en.wikipedia.org/wiki/Noisy-channel_coding_theorem

could have left it at the classical statement of the theorem with bullet #1. Then it goes on to say:

2. If a probability of bit error \(p_b\) is acceptable, rates up to \(R(p_b)\) are achievable, where

\(R(p_b) = \frac{C}{1-H_2(p_b)}\).

3. For any \(p_b\), rates greater than \(R(p_b)\) are not achievable.
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Hitchens vs. Hitchens

In some roundabout way I came across the debate of Christopher Hitchens vs. Peter Hitchens on youtube. If you search for it on Google you will find it.

These two are fairly quick on their feet, but almost opposite in style. Peter is more fair and circumspect yet outgunned at times, while Christopher is sharper and wittier yet full of bluster.
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president’s day

it is what it is


The Quantum Leap synthesizer sounds are commendable, but take a Herculean effort to program well.

Wired on the Gaussian copula

Because this article is spamming the internet today, I decided to read Li’s paper and learn what the heck is this Gaussian copula.

For five years, Li’s formula, known as a Gaussian copula function, looked like an unambiguously positive breakthrough, a piece of financial technology that allowed hugely complex risks to be modeled with more ease and accuracy than ever before. With his brilliant spark of mathematical legerdemain, Li made it possible for traders to sell vast quantities of new securities, expanding financial markets to unimaginable levels.

And anyway, here is the paper referenced in the article.
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halo orbit, Lagrange points, ITN

http://media.skyandtelescope.com/images/CandyFeb20_341px.jpgGreat stuff, this comet. I only recall seeing one comet in person, back in the 1990′s. Must have been Hale-Bopp. Now that was a rare one.

Comet Lulin is arriving from the far reaches of the solar system on a nearly parabolic orbit—”it’s almost as if it comes from infinity and goes back out to infinity,” he said.

This must have been one of these initially stationary objects then. Speaking of orbits, unrelated to comets, these so-called halo orbits are pretty amazing. They are orbits around stationary points in the gravitational field of three bodies called Lagrange points. L1, L2, and L3 are pretty obvious and therefore not that cool, but L4 and L5 surprised me and they are even stable… The application of going to an unstable Lagrange point and redirecting routing with low energy is even nicer.

continuous chord progression

Following up on a side note from this post, it is possible to construct continuous changes from one chord to the other by linear interpolation of their frequency envelopes (i.e., chord interpolation).

Here is an example in Mathematica.

A[f_] := Sin[2*Pi*t*f*220];

For example, one of the major triads is 4:5:6, and the harmonic minor triad is 6:7:9.

First, the two chords:

Play[{A[1260/1260] + A[1575/1260] + A[1890/1260]}, {t, 0, 1}]

Play[{A[1260/1260] + A[1470/1260] + A[1890/1260]}, {t, 0, 1}]

(Read the article)

almost dead?

I came across a story today of somebody who avoided a head on collision by moving to the next lane at the last moment, almost by involuntary reaction and without realizing what was going on. The full gravity of the situation always dawns on the survivor slowly, because everything happens so quickly.

This reminds me of my own near death experience. It was in the Bay Area near an airport in the middle of the night, I can’t remember where now. There was a very confusing road division where there were two left turn lanes, and one of them is somehow on top of some kind of surface rail (trolley) track running parallel to the lanes. I couldn’t see clearly at all. The traffic lights were not normal traffic lights, but some kind of symbol for each lane. Anyway, there were no dividers, fences, or barriers of any kind and I somehow ended up half on the tracks waiting for the light to turn green. Then in my rear view mirror, I see the bright lights of a train coming straight behind me. As the train comes ever closer, I get a feeling just like in a dream when something unreal is happening, a feeling of … “wait, this doesn’t make any sense”. So just like you might violently snap out of a dream in cold sweat, I stepped on the gas, ran the red, and moved into the next lane on autopilot, as the train whizzes by not more than a few feet beside me.

No horns, no noise, just a quiet train in the middle of the night. The whole thing still feels like sleepwalking to me and still doesn’t make any sense, but that would have been a terrible way to die.

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