liyan david chang http://blog.liyanchang.com Most recent posts at liyan david chang posterous.com Tue, 27 Mar 2012 10:01:00 -0700 Compressibility http://blog.liyanchang.com/compressibility http://blog.liyanchang.com/compressibility

Freshmen at MIT quickly deal with a weighty realization:

There is always someone smarter than you.

There is a corresponding drop in ego until one handles it and it's a freeing experience.

It's pretty quick realization when there are IMO, Siemens, and Fencing champions left and right. Moreover, while mere mortals buckle under the standard 48 units of credit, there are students who take double that with ease, often in the most rigorous majors like Math or Physics.

While impressive, the concentration in these majors is sensible because the course load is compressible, the slope of the intelligence/work plot.

Untitled-1

A class solely based on attendance would be an incompressible class; a human has very little advantage over a monkey.

In contrast, a compressible class is one that gets easier with intelligence. Math classes are often this way; there are proofs that take people seconds when the rest of us could stare at it with no progress.

Thus, the 96 unit students are able to compress their Math and Physics classes, while they would be unlikely to have much success if they tried to take that many Architecture or Management classes. 

Moreover, the slope is rarely linear and someone studying this more rigorously might apply Big O notation.

Lastly, it's also interesting to think about the unpictured case, where the slope is positive and intelligence is a detriment. The straightforward example that I can think of is a tricky and unsolvable puzzle where the laymen quickly gives up. 

 

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Tue, 27 Mar 2012 09:38:00 -0700 When worse is better. http://blog.liyanchang.com/when-worse-is-better http://blog.liyanchang.com/when-worse-is-better

I've been trying to read the seminal works in Computer Science and came across Richard Gabriel's "Lisp: Good News, Bad News, How to Win Big", or better known as "Worse is Better."

His core argument is to release early and get people to help.

It is better to get half of the right thing available so that it spreads like a virus. Once people are hooked on it, take the time to improve it to 90% of the right thing.

This explains the rise of transcompiled languages, like CoffeeScript or Snow, that translate one language to another. Performance would dictate for a assembly-outputing compiler, but would be missing the key point: people are looking for better ways of expressing themselves.

These new languages tout their syntaxtic simplicity and are quicker to release. (I'm currently writing a compiler and it's taking a significant amount of time just to release a half-baked language.) If they can hook enough hackers, they'll eventually help improve the performance.

It won't surprise me if the next big canonical language starts as a transcompiled language.

 

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Sun, 25 Mar 2012 07:12:00 -0700 Whoops http://blog.liyanchang.com/whoops http://blog.liyanchang.com/whoops

Z

There is probably an algorithmic trader madly recoding his system so it doesn't buy up Etch A Sketch (OART) stock like it did after a recent mention by Romney's aide.

 

 

 

 

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Thu, 28 Jul 2011 14:17:00 -0700 Bathroom Scales http://blog.liyanchang.com/bathroom-scales http://blog.liyanchang.com/bathroom-scales

I've been reading Paul Graham, of YCombinator fame, recently; less to understand startup culture, but more because he has a good sense of people & culture and some of his thoughts echo mine.

<http://www.paulgraham.com/cities.htmlhttp://www.paulgraham.com/love.html>.

On the other hand, he was writing about tablets and how he was impressed about their range of usages.

I wouldn't be surprised if by playing some clever tricks with the accelerometer you could even replace the bathroom scale.

Paul Graham (Dec. 2010) http://www.paulgraham.com/tablets.html

Knowing the large number of entrepreneurial types that follow pg religiously, I was surprised that a quick Google search didn't yield any results.

Not that I want to be the one to implement it, but I feel this this could be done with a rubber mat and your tablet. Place the tablet on the rubber mat and step on it. The movement, as measured by the accelerometer with dead reckoning, would be a good measure of the mat's compression, of which you know the physical properties.

Now, the problem is shipping a mat along with your app. An alternative is using an everyday compressible object (like a folded towel, bed, or shag carpet) that would just require some calibration and alignment to understand the property of the material. Place any known weight, say a 20lb bag of rice on it or a dumbbell, and you should be able to calibrate.

Since a usable number probably just needs to be accurate to the pound (as proven by the use of analog scales which require calibration and are hard to read), this method just may be accurate enough.

To flesh this out though, one would have to think more carefully about the market of bathroom scale owners though, as there seems to be a trend to digital scales with decimal accuracy. Alternatively, people might just buy it for the giggles, which on the app store is unfortunately a common reason.

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Mon, 28 Mar 2011 05:43:00 -0700 Untitled http://blog.liyanchang.com/47606329 http://blog.liyanchang.com/47606329

One of the new necessities is that a world comprising several states of comparable strength must base its order on some concept of equilibrium — an idea with which the United States has never felt comfortable.

H. Kissinger in Diplomacy p.19

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http://files.posterous.com/user_profile_pics/1914811/DavidChang.png http://posterous.com/users/10z5ZQWBwKR Liyan Chang Liyan Liyan Chang
Sun, 27 Mar 2011 18:17:00 -0700 Zurich http://blog.liyanchang.com/zurich http://blog.liyanchang.com/zurich

I was in Zurich last weekend and it was such a nice little city. Granted, I only walked around Old Town, but you have to appreciate the combination of old time charm with clean modern design. Yes, even the Pizza Hut ads were designed using Helvetica and the Swiss Grid. The fact that I ate where Lenin did (Cafe Odeon) and visited James Joyce didn't hurt either.

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http://files.posterous.com/user_profile_pics/1914811/DavidChang.png http://posterous.com/users/10z5ZQWBwKR Liyan Chang Liyan Liyan Chang
Sun, 27 Mar 2011 15:14:00 -0700 Chrome Gripe http://blog.liyanchang.com/chrome-gripe http://blog.liyanchang.com/chrome-gripe

While I'm at it, I'm going to gripe a bit about Chrome.

First, lets begin by setting up some formalities. I've been very impressed by Google Chrome, both in terms of product but also the speed of their market penetration. The increased competition by a well funded and important player has really increased the innovation in this area.

As with all things, I'm not going to spend as much time on the things that they have done right and instead nit pick. I realize I'm sitting in the cheap seats and for that, I'm sorry. If you are a chrome developer and want to know what I think is done well, feel free to email me ;D.

Gripe 1: Delay after opening a background link

After opening a link as a background window, the page that I'm viewing stall for a significant and noticeable amount of time. I often read a page and open interesting links to flip through later and stalling interrupts my train of thought. My uneducated guess is that opening a new process has something to do with that lag, but isn't unsolvable. The mere fact that I opening it in the background means that I don't want it immediately. Feel free to put it on the backburner but I want the current page to remain reactive.

Gripe 2: The Back Button

After going back a page, it takes a chunk of time for Chrome to reload the page and to scroll to the section of the page that I was at previously. I haven't taking a look if they do a full reload or a cache load, but either way, this is just irksome. I want to go back, instantly, without seeing the top of the page and then scrolling.

Not Really a Gripe 3: The Gradient on the Tab

Have any of you noticed that when you hover your mouse over a tab, it does a bit of a gradient that follows your mouse? I hope that some engineer had some fun doing that because that doesn't add to the user experience in any imaginable way.

I've tried to screenshot it, but it is still very subtle. On the first picture, my mouse was hovering over the left side of the tab and on the second, the right.

As a side note, has any one noticed the similarities between elections and browser selection? IE as the large, well funded candidate that tries to be everything to everyone and fails. Opera, as the candidate that you know will never make it out of the primaries, but is able to bring some important issues to the debate, such as web standards. The large majority of people using what they have or have been told by their friends to use, without really paying close attention to the features. Granted, I've got some thinking and cleaning up to do with this idea, but if I was working for one of those companies, I'd definitely spend some time thinking about how elections are won and lost, how issues get media coverage, and how to reach out to swing voters.

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http://files.posterous.com/user_profile_pics/1914811/DavidChang.png http://posterous.com/users/10z5ZQWBwKR Liyan Chang Liyan Liyan Chang
Sun, 27 Mar 2011 15:14:00 -0700 Techie Update http://blog.liyanchang.com/techie-update http://blog.liyanchang.com/techie-update

Well, as you all know, I'm a Computer Science major, which invariably leads to the "Why are you here?" when I tell my fellow exchange students here at Sciences Po, a political science school in Paris.

I've been enjoying the life of a humanities major and wrote pages upon pages for class. However, I seem that having a technology relapse this weekend.

 

First, Firefox 4 was released and while I'm a bit late to try it, I have to say that I can see marked improvement in terms of user interface. To tell the truth, in the recent browser wars, I've almost written off Firefox. Chrome made a big splash, has been updating often, and has made significant inroads in terms of a userbase. Opera, my perennial favorite, is actually being mentioned in the reviews and comparisons, though it still irks me that many people misattribute many of the innovations that Opera has brought, like tabs and speed dial.

In fact, there was a time that I disliked the Mozilla Firefox interface enough to tell a Mozilla recruited that my browser of choice was Opera, not Firefox. Nonetheless, I'm glad to see that the design team has been more user-centric. Now, I'm sure it was a group effort, but a round of applause for Aza Raskin, ex-Head of User Experience at Mozilla. I've had the fortune to have talked with him briefly during the interview process, still read his blog, and have to say that I see a lot of his influence on the new changes, even in the small details. For instance, the "undo" buttons that appear when you remove an addon or the Mozilla Labs trials that made it in to the final release.

While I'm not ready to set Firefox to my default browser, I no longer feel uncomfortable with it open and I'll continue to play around with it.

 

Second, Project Euler. It's a collection of math problems that you solve with code. I signed up a year ago and been doing them off and on. I've brute forced a couple of the easy ones, knew some of the tricks for others having done math team, and I'm now a Level 2. It was however able to keep me up late into the night and I'm now out of problems that are reasonable to solve naively. I'll probably come back in a couple months and try for another level. (This badge thing is very motivating. I have a better understanding for people who get caught up in Farmville, WOW, or Medal of Honor.)

 

Lastly, I'm not sure how many of you played with Logo as a kid, but it's built into the Python standard library. It started as a way to teach kids programming and it actually had this big robotic turtle that would move and draw on command before becoming a computer program. I have fond memories with this. :D

Image_6

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Tue, 15 Mar 2011 05:53:00 -0700 Heavy Metal http://blog.liyanchang.com/heavy-metal http://blog.liyanchang.com/heavy-metal

There are all sorts of cultural differences that I'm discovering here during my study abroad. One of which is common use of cash and the second is the large denomination coins.

First, I think that a large part of I'm seeing a lot of cash usage is because the section of Paris that I live in is a bit poorer and as a result have more reliance on cash. For overall usage, I'm getting mixed signals. Once a French student asked me and another American exchange student if we were impressed by the heavy use of "carte bleue", a French system of quasi-credit debit cards and she immediately protested so perhaps I'm not the only one who feels that way.

The second issue on money is that they have 2 Euro coins. As an American, where the largest common coin is a quarter, a 2 Euro coin psychologically feels like a trivial amount. It's been one of those small things that irks me here.

 

Now, I've found a Government Accountability Office (GAO) report that finds that the US, while incurring some initial fixed cost, would save $5.5 billion dollars by switching to the dollar coin. The Euro is not alone. Australia, Canada, and New Zealand have all switched over to 2 dollar coins, which are all worth more than $2 USD due to exchange rates. You can read the summary or the full report

Part of me thinks that the American people are such traditionalists that this change would require a significant amount of political capital to remove the dollar bill, not to mention the initial costs in this economic doldrum. One only needs to recall the fight that happened over the removal of pennies, and that proposal wasn't nearly as far reaching.

 

I think that the question that I'm wondering is what would happen if we started moving to an entirely cash free economy. What are the effects of removing cash entirely from the US economy?

First, let's address some of the simple issues. Merchants would face increased fees from the credit and debit card companies but it would reduce the labor and speed up queues. In my mind this is a wash. Consumers would no longer have to carry around cash, though it would likely encourage them to spend carelessly.

Tax evasion would be much more difficult as unreported cash transactions would no longer be possible. I'm not a law enforcement agent, but from my extensive television research, it seems that certain forms of crime, laundering, drugs, illegal immigration, would be more difficult as transactions would be easier to track.

However, the sole use of electronic payments would raise some issues on the less established. The lower income brackets, which have been traditionally underbanked, would find this change a bit difficult.

Small business who are not established would find that the cost of starting a business would slightly increase. My gut reaction is that simple and cheap credit card readers would become available. I've payed another student with my credit card via paypal and credit card readers are being made as addons to iPods.

 

A quick Google and Google Scholar search didn't net any interesting results so I'm currently unaware of any serious thinking on this matter. Just a curiosity.

Update: Link to the summary and full report added.

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http://files.posterous.com/user_profile_pics/1914811/DavidChang.png http://posterous.com/users/10z5ZQWBwKR Liyan Chang Liyan Liyan Chang
Mon, 21 Feb 2011 16:01:00 -0800 Not the only exception http://blog.liyanchang.com/not-the-only-exception http://blog.liyanchang.com/not-the-only-exception

A friend of mine told me that characterizing American arrogance, the root cause for international disdain for America, is simple. While other citizens are proud of their countries, only Americans think that America is exceptional.

I pondered this point, wondering if it was indeed the concept of "American Exceptionalism" that grates foreign sensibilities. It may be true that our hubris is what makes us unlikable abroad, America is not the only historical user of the word "Exceptionalism".

Both the French and the USSR have used this concept. I think that it tends to afflict nations with strong ideological underpinnings that believe their ideas are superior and exportable.

Nevertheless, a couple open questions that I'm thinking about:

  1. Is the cause of international disdain for America rooted in our arrogance?
  2. Is America overly proud? Either on grounds that we have no justification or that we have justification but should nevertheless be humble.
  3. Is American exceptional or will we too succumb to Paul Kennedy's fall of the great powers?

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http://files.posterous.com/user_profile_pics/1914811/DavidChang.png http://posterous.com/users/10z5ZQWBwKR Liyan Chang Liyan Liyan Chang
Mon, 21 Feb 2011 15:39:40 -0800 So it begins... http://blog.liyanchang.com/so-it-begins http://blog.liyanchang.com/so-it-begins I've always wanted to start a blog but none of my stillborn attempts have survived past their inaugural post. Anyone whose talked with me knows that it's not for a lack or opinions and classmates who witnessed my loud participation during grade school debates knows that it's not a lack of self-confidence either.

My current theory why I've failed to maintain a steady blog presence is what I call the "Facebook effect". As this generation callously reveals personal details to the unforgetting and unforgiving internet, we compromise Father Time's ability to erase "youthful indiscretions". Our children and grandchildren will be aghast when their find out our likes in music, fashion, and sports archived forever.

More interestingly, there has yet to be a politician whose teenage years coincided with the advent of Facebook. The American people have long expected a shiny veneer on their politicians and campaigns have been willing to lie, spinning their candidate's history to demonstrate perfect judgement and character. While this charade can last when their childhoods are clouded by time, the next generation of politicians will not have this luxury. Currently, only the top leadership is subject to the intense press vetting that brings long-closeted skeletons to light, such as George Bush's report cards and marijuana usage. However, the internet makes such inquiries much easier for future reporters.

My guess is that underage drinking will be the most prominently featured item. A common theme in conversations with other students here at Sciences Po is how prudish America is about public affection and alcohol consumption in comparison to the rest of the world (sans The Middle East). As most college students are in violation of drinking regulations and open post party photos, this is probably the easiest to exploit. This has already been used by some corporations in their hiring processes.

In light of how savvy politicians have been forgiven for adultery, corruption, and other dalliances, perhaps this fear is overstated. In this arena, I foresee two possibilities: First, the political mudslinging happens at more levels than just the presidential election and second, that the populace tires so much of it that they become more forgiving about it and allow politicians to be transparent about their failings rather then avoiding them.

However, I can't seem the dodge the feeling that everything that I do online is recorded and forever subject to scrutiny. While it takes an enormous ego to believe that a reporter or historian would be interested in scrutinizing my writings, it still has a paralyzing effect to think that my unborn children, unmet business partners, and future friends could all be reading.

I do believe that revealing my thoughts about life will led to critique, mockery, and correction in both present and future times, but I begin in hopes that having to honest with myself and others will make me a better person.

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