Category Archives: General

Thinking

I don’t think that most people, or even most gifted people, think the same way that I do. I’m not sure whether that’s an asset or hindrance. On the one hand, there’s “you can direct your thoughts so precisely?” On the other, there’s “you mean thinking tires you out?” and “you can only think of one thing at a time?”

Stress and grad. school

You know there’s something wrong with the system when the people in charge say things like this:

“Jorge Cham’s talk was humorous and helpful. His cartoon strip has been a giant plus in helping graduate students acknowledge and cope with the stress they experience.”

– Isaac Colbert, Dean of Graduate Students, M.I.T.

Rather than trying to reduce the stress the students feel in the first place!

The paradox of too much space

You know that uneasy feeling you get when moving to a much higher resolution on a monitor?

I now call this the “paradox of too much space”. That phrase drew no hits from Google. I’m happy; I finally discovered an original phrase 🙂

Offices

I figured out why I hate offices: I focus entirely on what I’m doing there, with no personal diversions (save checking my email). Office environments are not built for this sort of thing, so I get flow going, finish my work quickly, and proceed to stare at the walls… for SEVEN HOURS EACH DAY.

At home, I’d finish the work in the same amount of time, then write music, read, program, etc. until I received more work.

Sapir-Whorf Hypothesis

I have quite a few problems with this hypothesis. It isn’t that the hypothesis is flawed – quite the contrary, actually: this hypothesis is so obvious that it really doesn’t deserve to be named after two people who, incidentally, were not the first to discover or write about it. Another problem I have is that it’s needlessly specific. It can be summarized in three words as “language influences thought”, when a much more general hypothesis (the one I arrived at as a child and later incorporated into my psychological postulates) is “expression influences thought”. Finally, the hypothesis is needlessly unidirectional: to argue that expression is not a product of thought, formal system that it is, is ludicrous. Therefore, an even stronger statement is “expression and thought influence each other”.

I needed to be born 50 years ago, when the obvious things weren’t all discovered yet. But then, perhaps I would have died in childbirth had that happened.

Grading by Z-score.

A recent discussion with a friend reminded me of an idea I had in high school: in order to encourage students to focus on course subject and content rather than difficulty and to reduce the variability in the grading system based on instructor, the current letter grading system should be replaced with Z scores: (numeric score or GPA – mean) / standard deviation, where the mean and std. dev. are grouped by course and professor (but cumulative over semester). Consequently, lower scores in more difficult courses would be competitive with higher scores in less difficult ones. Additionally, as I’ve seen twice, there are professors (and they were algorithmists both times) who simply do not give out “A” grades. Thus, under the current system, achieving a perfect GPA is as much a matter of avoiding these professors’ courses as it is a matter of performance. Under a system that takes the mean grade of the professor into account, however, they could not harm students GPAs in this way, as their means would be lower than other professors’.

Searching academic papers

While doing a literature review for online decision tree construction algorithms, it struck me that Google’s pagerank model, though designed to model the importance of pages as if they were papers in academic journals, is backwards for certain types of literature reviews. For example, suppose I were looking for state-of-the-art research rather than “classic” results in the field.

Using the pagerank model, papers that are cited often will have high pageranks (depending on the number of citations and pagerank of the citing papers), while most citing papers will tend to have lower pageranks, especially if new. However, if I am interested in the state-of-the-art, I would be most interested in papers that build upon many previous results; that is, papers with many outgoing citations. I would also like to eliminate very frequently-cited sources (such as The Art of Computer Programming or Introduction to Algorithms, which are cited for such trivial concepts as the definition of a tree) from the analysis, as those citations have lost almost all meaning.

This is the exact opposite of what the PageRank algorithm does as it is described in “Anatomy of a Large-Scale Hypertextual Web Search Engine”. It is closer to techniques such as tf-idf if anything.

Quantum immortality

From a discussion on Wikipedia, describing the implications of the “quantum suicide” thought experiment: that a physicist whose consciousness does not end when it is probable for it to do so would end disabled or disfigured in the majority of universes in which he survives:

“Here’s another possibility: in the majority of universes where the physicist survives, there simply is no explosion. If the explosion does occur, it is highly probable that the physicist’s body would be damaged even if he miraculously survives. This would probably shorten the physicist’s lifespan, thus pruning the number of potential universes in which he endures. However, if the weapon does not detonate at all, the physicist would have an excellent chance of survival in both the short and long terms.

I suppose that this question essentially asks whether the strategy followed by the universe is greedy. I confess that I don’t understand enough of quantum mechanics to judge whether a non-greedy strategy makes sense. It’s appealing from an algorithmic point of view, however.”