The traveling saleshuman

As part of the homework for the course I was TAing this summer I assigned an algorithm related to the Traveling Salesman Problem (TSP). The students were asked to implement a relatively simple algorithm that computes a 2-approximation of the solution to an instance of the TSP1. I was dissapointed, although not surprised, when I started receiving questions from students about the Traveling Salesperson Problem via email. I don't know if their textbook used this ridiculous renaming of the problem, or if the students themselves have been sufficiently indoctrinated with Political Correctness that they couldn't bring themselves to type the word "salesman", but either way it made me want to cry. It's one thing to use somewhat different terms (e.g. chair instead of chairman) to avoid the appearance of bias in the world of oversensitive paranoia like politics or business, but it's quite another to make up idiotic words whose only purpose is to annoy people and to show how diversity-sensitive you are. Never mind that the word man was originally gender neutral, the words wer and wyf were used to refer to male humans and female humans respectively2. Which means that words like mankind aren't used to refer to the human race because of patriarchical opression, but because that is the actual meaning of the word. Why should we throw away perfectly good words because of fanatic uninformed revisionism? It would be equally valid, and much simpler, to realize that the word "man" can be gender neutral, and has been historically, rather than to try to eliminate every single word like mailman or man-made with "modern" words like letter carrier. People could just realize that the history of male dominance in society does not mean that the gender neutral meaning of the word man has been abolished, and then get on with their lives. This reminds me of a pamphlet on political correctness that was given out by the Operations Research and Industrial Engineering department at Cornell to their TAs. It had numerous examples of phrases that were considered insensitive. One of these was the idiom "black sheep". Yes, you read that right. Apparently the phrase "black sheep" is now racist. Give me a break. 1. The Traveling Salesman Problem (TSP) can be stated as follows. Given a set of vertices (i.e. cities) and a set of edges (i.e. roads) connecting them, where each edge has a certain weight (i.e. distance to travel), what is the order in which the vertices should be visited so that every vertex is visited, and the sum of the weights of the edges used is minimized? A 2-approximation for this problem is a visit order that is guaranteed to have a weight within a factor of two of the weight of the optimal order.

Paraphrased, but still funny

Salam E. Skinner: I don't understand why [butterfly knives] are illegal. I mean, how is it different than a kitchen knife? The Broken Neck Man: Because it's concealable. You could have it in your hands and nobody would know. And then you flip it open, and you have a knife in your hands. The Awkward Silence: Yeah, and then [they] lose initiative.

A Consumer's Lament

If a coin-operated washing machine can tell the difference between a Canadian quarter and an American1 one, then why can't the bank where I obtain my rolls of quarters do the same? 1. Pardon my ethnocentrism. A United States one.

Trust us.

We know what's best for you.

Subtle Changes

Those of you from the Boston area probably know that Fleet Bank was bought out by Bank of America in the recent past. I noticed a few interesting differences between Fleet's online banking and Bank of America's online banking. When I used to use Fleet's online banking for my credit card, I used to log in and immediately see my balance. I could follow the "Pay Bill" link and it would take me to a web form to make payments. This web form would have my default checking account set to make the payment from, and the amount to be paid would be the current balance. Bank of America's payment application is a little different. In order to pay, you first have to select a specific bill to pay. Each of your unpaid monthly bills is presented to you to choose from. So far so good. When you have selected the bill, a payment page appears, with some interesting default values. The default date for the scheduled payment is not the next business day, but the last day before the payment is actually due. The default amount to pay is not your balance, but the minimum allowed payment. Your current balance appears nowhere on this page for you to refer to. Some may argue that these different choices for the default values in the payment form are just a matter of taste, but the more cynical might think that they are a subtle attempt to influence the way a customer uses their credit card.

And then there were N - 1

I just got home to Boston, and my (mother's) car is full of all my crap. Highlight of the trip: A vending machine at a rest stop demanded 1.80 USD for a single bottle of water (or soda).

Les Adieux

I just saw Wicked Hot Engineering Chick in the Duffield atrium. Probably for the last time. Sigh.

Why Supervillains Use Linux.

Phe4r th3 P3ngu1N.

And all I had to all this time was ask...

Apparently Blogger does support SSL login. I didn't find a link to it anywhere, but if you just add the 's' to the URL you get the happy yellow lock thing in your browser. It's a useful bookmark to have if you don't like your password being sent all around the internet and back in plain-text1. 1. I recently found out that some websites that don't use SSL don't actually send your password in the clear. They use javascript to compute a hash of your password, and that's what they send. I like this trick. It's clever. I never thought of using javascript to compute the hash of the password before it is sent, rather than at the server, as it is usually done. So your account for that particular site can still be hacked using just a plain old packet-sniffer, but your actual password won't be compromised, which is a good thing if you happen to use the same password for your online banking or somesuch thing.

A Social Dilemma

I read somewhere, I don't remember where, that being fat is like being invisible. This is the way an obese person described it. Apparently, since people are trained "not to stare" at people who look out of the ordinary, they end up avoiding eye contact altogether. So if you look like you "have a problem" nobody acknowledges your existence as you walk down the street — no eye contact, no human signal of any kind. It's as if you didn't exists. That's what I read, anyway. There is a young handicapped woman that I occasionally see when I take the bus to campus. As people get on ahead of her they all move to the back, ostensibly to leave room for her wheelchair1 in the front. This essentially leaves her alone in the front half of the bus, facing forward, so that she can't see anything or anyone except the back of the driver's head. Remembering what I had read in the past, I decided to sit in the front. In this part of the bus the seats are sideways, meaning that they face toward the center, not forward. This means that my legs were taking up room in the aisle. As she drove past me she apologized for forcing me to move a bit so that she could pass. Clearly she had no need to apologize, I was in her way; I should have been apologizing. Yet, because she did apologize, I felt that she must have been thinking2 either, "Is this guy blind? Can't he see he's in my way?" or "I hate being in a wheelchair. I'm always in people's way". Neither result is good. So was it wrong for me to sit in the front? What do I do? Do I get in her way? Or do I pretend she doesn't exist like everyone else? 1. Pardon my insensitive language. I meant mobility aid. 2. Obviously she was probably just being polite, but like I said, this is what I felt.

Digging holes rocks.

A few interesting links. An awesome bank heist. An interesting acusation. A revealing medical study.

Let's get it on!

I saw Runaway Jury a few weeks ago. It wasn't a bad movie overall, but that's not why we're here. This movie has an awesome fight scene. A woman is attacked by a man and she actually fights back. I don't think I've ever seen that in a movie, not counting action/sci-fi movies. It was refreshing and liberating. I was right, and all the other movies were wrong. Every time I watch a movie and a woman gets attacked my suspension of disbelief is totally wrecked. In most movies they just give up and the scene is done with. They just kind of whimper a little bit and then get 'captured' so the hero can rescue them. It's so frustrating to see a fight in a movie when you know a character could easily do reasonable things to survive or escape, but they don't because it's not in the script. When the fight scene in Runaway Jury began I was already rolling my eyes, waiting for it to be over with so I could find out what consequences the writer needed for the plot. But that didn't happen. The female character actually resisted her assailant and did everything in her power to try to escape harm. The conclusion of the encounter was believable because the characters realistically brought it about. Most movies treat these kinds of scenes as a tired formality, and they end up with nothing more than a blatant plot device¹. These movies suck. 1. Then again, most movies are nothing more than tired formalities and blatant plot devices.