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Monthly Archives: October 2011

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Thanks Abe ūüôā

 
the most interesting blog in the world

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I know that reading huge blocks of text isn’t for everybody, so I’ve included what I think is one of the best visual representations of information constructed by man. Below (click on it to see it in its¬†unadulterated, full sized glory) is a picture of a map for the London underground. At a glance, knowing nothing about London, I can see that to get from, say, Northwood to Kingsbury, I have to transfer at Wembley Park. It’s clear, simplifies a great deal of complexity, wastes no space at all, and packs information about connections between locations, routes, transfers, times of service, and transit agencies into a single image. It’s beautiful.

I learned about two interesting, if mostly unrelated concepts lately. I’m sure that they’ll be useful to me at some point in the future.

The first one is called a Wilson score. Wilson scores are useful to sort a set of reviews or ratings in a meaningful way. Let’s say you run some sort of e-commerce site (we’ll call it Omazan) which lets buyers leave either thumbs up or thumbs down ratings for any given product. There are two common ways of sorting these that are totally wrong.

  1. # thumbs up – # thumbs down: Consider the case where you have an item that has 20 thumbs up and 10 thumbs down. This means that 2/3 of people like it. Suppose there is another product that has 500 thumbs up and 490 thumbs down. This means that only about half of people like it. However, both of these products are rated equally given this heuristic.
  2. # thumbs up / # total ratings: A simple average works well in many cases, but not very well for small numbers. Say you have a product which has received no thumbs down, but 1 thumb up, and a product which has received 500 thumbs up and 1 thumbs down. The first product, which has much fewer ratings, will be rated higher than the second product, and it doesn’t make sense to order them this way.
How does the Wilson score work? Essentially, you plug the reviews you have into the formula, as well as a confidence score. You will get out a confidence interval for that score (in layman’s terms, you have a confidence interval at 95% of what the actual distribution of ratings is). If you take the lower bound of this confidence interval, it’s a pretty good way of ordering things. Here’s some psuedocode to calculate it (assuming a magic function that can look up a Z score for a confidence interval):
def wilson_score(num_positive, num_negative, conf):
    num_total = num_positive + num_negative
    if  num_total == 0:
        return 0
    z = lookup_z(conf)
    p_hat = num_positive / num_total
    return (p_hat + z*z/(2*num_total) Рz*sqrt((p_hat*(1-p_hat)+z*z/(4*num_total))/num_total))/(1+z*z/num_total)
Useful trick.
The second thing is something called an H-index. H-indices are used to calculate how awesome a scholar is. An H-index is a value H which is the highest number for which H or more publications have received at least H citations. So for example, if I have published 8 papers, and one of them had been cited 20 times, but the other 7 had been cited only 7 times, I would have an H score of 7. If each of those seven had been cited 6 times each, I would have an H score of 6. This serves to be a valuable measure of widespread impact, rather than blockbuster ability; sort of a way to weed out the one hit wonders.

Persimmons in Seoul, courtesy of the Boston Big Picture

An incomplete and unsorted list of pieces of classical music I associate with certain emotions:

  • American Quartet, Antonin Dvorak: longing
  • An American in Paris, George Gershwin: playfulness
  • Quiet City, Aaron Copland: loneliness
  • String Quartet No. 2, Alexander Borodin: nostalgia
  • La Puerto del Vino, Claude Debussy: mystery
  • Adagio for Strings, Samuel Barber: mourning
  • Piano Concert no. 3, Sergei Rachmaninoff: weariness

Ecclesiastes is a book of poetry in the Old Testament of the Bible. It was inferred that the author of the book is King Solomon, the ruler of Israel at its peak power in ancient times. Whether it truly is written by the greatest king of Israel or not, it’s a beautiful piece of writing by any standard, and it’s brought me a lot of comfort to read the words of an author 2000 years ago who experienced the same human feelings of doubt and uncertainty about the role of mankind in the universe.

There is a time for everything, and a season for every activity under the heavens:

a time to be born and a time to die,
a time to plant and a time to uproot,
a time to kill and a time to heal,
a time to tear down and a time to build,
a time to weep and a time to laugh,
a time to mourn and a time to dance,
a time to scatter stones and a time to gather them,
a time to embrace and a time to refrain from embracing,
a time to search and a time to give up,
a time to keep and a time to throw away,
a time to tear and a time to mend,
a time to be silent and a time to speak,
a time to love and a time to hate,
a time for war and a time for peace.

This is an absolutely fascinating read about the current state of leadership in the CCP, and provides a lot of insight into chinese politics.

Over the past few months, several people have written asking me to offer a short ‚Äúprimer‚ÄĚ on China‚Äôs upcoming leadership transition, which begins next year.¬† The handover to a new president and premier has generated plenty of speculation in the press, about who the leaders are and what is will all mean, but sometimes it‚Äôs useful to go back and fill in the very basics, since China has a unique and in some ways¬†quite confusing political system.

http://chovanec.wordpress.com/2011/05/08/primer-on-chinas-leadership-transition/

Hideaki Akaiwa

This guy is named Hideaki Akaiwa. He is 43 years old, and has an office job¬†just outside the port city of Ishinomaki in Japan’s Miyagi Prefecture. He also has one of the most inspirational stories I’ve read about in my life.

It’s Friday, March 11, and Hideaki is doing work at his desk. It’s 2:45, and he has no idea that in about a minute, one of the top five earthquakes in recorded human history is about to devastate Japan, sending tsunami waves of 40.5 meters crashing into Ishinomaki. Torrents of water will sweep the city, pushing cars around, flooding buildings, and causing widespread panic. In a matter of minutes, Ishinomaki goes from being a city to a lake, 10 foot deep in water. Hideaki’s wife is somewhere in the middle of that lake. They’ve been married for just over 20 years.

Instead of running away and waiting for assistance from the army and other social services, Hideaki dons a wetsuit and scuba gear and rushes into the torrential currents, swimming around cars, chunks of wood, and twisted shards of metal that used to be houses. At this point, it’s pitch black, but he somehow manages to navigate underwater to his house. He finds his wife trapped in an upstairs room of their house, panicking, with only a small amount of air left, and manages to pull her to safety.

He’s not done though. After rescuing his wife, he finds out that his elderly mother is unaccounted for in any rescue shelter, so he puts on the scuba gear and goes out to look for her. Four days later, he finds her in the upper levels of a house and manages to rescue her also.

For a week after the tsunami hit, he continued to help out with the relief effort, looking for survivors and assisting in the relief effort.

What a badass.

From Eric Stinson, via the Atlantic:

‘True love’ was a construction of Western-style nobility courtship rituals, enhanced by centuries of media, nearly as insubstantial and potent as Coca-Cola’s Santa Claus.

Full commentary is here: http://www.theatlantic.com/life/archive/2011/10/love-on-the-internet-dating-in-the-age-of-the-profile-image/245915/

Ever since I discovered that it was possible for me to make a delicious steak in less than 10 minutes with a tiny amount of effort on a simple stove, I’ve been going steak crazy. Steak is surprisingly easy to perfect. Here’s my steak recipe:

Stuff you need:

  • A couple of steaks, roughly 1 inch in thickness. I’ve used sirloin and ribeyes, but this should work well with any relatively fatty cut.
  • Salt and pepper
  • Dried garlic, garlic powder
  • (Optional) Dry mustard
  • Olive oil
How to do it:
  • Make sure your steaks are at around room temperature. Leave ’em outside for an hour or so if they’re not and come back later.
  • Cover both sides of your steaks with olive oil
  • Generously rub pepper all over so it sticks to the oil. I have a mini pepper grinder, and I use about 6 twists per side
  • Coat steaks in salt. Probably much more salt than you would imagine. You want a thin layer of salt all over the steak. Imagine what your leg looks like after going to the beach, standing in water, walking through the sand, and drying off after a couple hour — you want that much salt all over your steak.
  • Smear a teaspoon or so of dry mustard on both sides.
  • Turn up your stove to high. You want as much heat as possible, so really crank it up to the highest of high settings. You should heat a pan this step too — I’ve gotten the best results with cast iron, but it’s worked out pretty well with a simple nonstick aluminum pan as well.
  • Open some of your windows, turn on your stove fan, take the batteries out of your smoke detectors, etc
  • Toss your steaks on the pan. There should be a lot of hissing and brouhaha, but try not to poke or prod your steak too much, just leave it there.
  • You’ll want to leave it on the pan for somewhere between 2-3 minutes per side. Play around a little — this is probably the hardest part, where literally 10-20 seconds can transform your steak from medium rare to nuked, so just try different things and look at the coloring on the side of the steak to develop intuition on when to take ’em off the stove.
  • Enjoy!