Inception

The movie is great. Go see it. What I'm about to write will be entirely spoiler free.

Inception will leave you distrusting your own perceptions in the manner of Descartes's Demon, more so than The Matrix ever did. It does this I think because the experience of the characters in the movie entering and leaving dreams is so similar to our experience entering and leaving the movie. "Waking up" from a good movie is a very similar feeling to waking up from a dream.

When we talk about "suspending disbelief," it isn't supposed to be something you do, but rather something that happens automatically if the movie succeeds in drawing you in. When dreaming, we tolerate wild violations of physics and causality without it ever decreasing our emotional involvement. The objective of a good movie is to tap into that level of credulity, and it wouldn't surprise me if someone discovered that the same pathways in our brains are involved.

When Christopher Nolan was writing the dialogue about how addictive it is to be an architect of dreams, he must have been really talking about is how addictive it is to be an architect of shared dreams: movies.

Men's Wearhouse is missing a major business opportunity.

Every male in the U.S. who goes to a prom or is someone's groomsman has likely been fitted for a tuxedo at the Men's Wearhouse. Theoretically, the Men's Wearhouse should have the most comprehensive database of men's sizing information of any company. There have been a lot of weddings among my close friends this year, and I assumed that after the first fitting I'd be able to rent subsequent tuxes without going to the store in person. Amazingly, according to one of the attendants, they throw away all information about the customer after 6 months.

This loss goes beyond convenient tuxedo rentals. With this much information about me, they could be delivering clothes custom-tailored overseas to my doorstep at a price no other company could match. That much opportunity is certainly worth the cost of a few dozen more machines. Ancillary data produced by your business can become more valuable than the profits from the business itself. Don't throw anything away.

Janelle Monáe (Wow)

Imagine if Lauryn Hill became a geek, teamed up with Outkast, and wrote two concept albums about an android uprising in the futuristic city of Metropolis. The result would sound something like Janelle Monae's inaugural two albums, Metropolis, and The ArchAndroid, the first three acts of a six act story. The songs flow seamlessly (literally) from one to the next, usually jumping genres in the process. She can wail, she can scat, she can croon, she can rap, she can dance (oh she can dance), and she can sound like GLaDOS when necessary. Orchestral interludes bookend the chapters; In one, she puts words to a snippet of Claire De Lune.

Pitchfork loves her too. Historically, the intersection of the albums I like and the albums they bother to review has been approximately 0, so these two recommendations are about as independent as they come. Go have a listen! Every track can be heard for free at the links above.

My favorites so far: Sincerely, Jane, Tightrope, and Oh, Maker.

Tax-time gripes

California Use-Tax

It's really not reasonable for me to try to add up all the money I've spent online (but only on items used in California, not those purchased as gifts to someone out of state.) This is the largest expenditure for me outside of rent and travel, and I don't remember everything I've bought and from where. Mint.com and searching for "receipt" in gmail helps, but it's really a lost cause. I do my best, but it seems most people I talk to don't bother, despite it being the law. This is by far the most time-consuming part of filing my return, and only hurts me to do so.

A few things confuse me about it.

1. Is shipping and handling included in the taxable portion? It's not "used" in California.
2. Do online retailers have enough information themselves that they could provide some sort of automated assistance in tallying these?
3. Have the courts decided whether use-taxes are constitutional despite being a tax on inter-state trade?
4. Am I a chump for bothering?

Passwords

Filing my taxes inevitably involves getting data from financial institutions that I haven't had any interaction with all year, and thus, remembering my various passwords. If you are designing a password system, please don't place restrictions on the content of the password. It's your responsibility as an administrator to keep your users' passwords from being brute-forced. Do not offload this responsibility to them.

Arbitrary restrictions I've seen today alone while trying to get forms from various financial agencies:

• Must have at least 1 number.
• Must have at least 2 numbers.
• Must have at least one capital letter and 1 number.
• Cannot have special characters.
• Must be greater than 6 characters, but no more than 15.
• Must be greater than 6 characters but no more than 8.

If I can't have a small secure set of passwords to use everywhere that I can reasonably remember, I'm just going to email them to myself, thus defeating every high-minded security best practice you are trying to implement.

Google can render your equations for you!

In my last post I mentioned that Knol and Google Docs now have equation editing. What I didn't mention is that this is an undocumented feature of the public Google Chart api, and it's easy to use. For instance, if I wanted to include the Schrödinger equation on this blog. I would construct an url like this:

http://chart.apis.google.com/chart?cht=tx&chf=bg,s,FFFFFF00&chco=AACCFF&chl=i\hbar\frac{\partial}{\partial t} \Psi(\mathbf{r},\,t) = \hat H \Psi(\mathbf{r},t)

Put your code in the chl parameter. The chf parameter lets you specify a background color in RGBA, chco lets you set the foreground color in RGB. When you drop it in inside of an image tag you get this:



If you anticipate making 250,000 calls to the chart server a day, contact Google first at chart-api-notifications@google.com. There's no limit to how much you can use it, but they reserve the right to turn you off.

Simple Simhashing, My favorite trick.

Knol got equation editing a few days ago, and to celebrate I've written up a knol on one of my favorite CS tricks, simhashing using sets. It's a technique I picked up at Google, and it's extremely useful for grouping together similar things in a large dataset.

Suppose you have a huge number of items that you would like to group together by a fuzzy notion of similarity. Suppose the only tool available to you is a key-value store. Suppose you only have the resources to consider each object once. Never fear, simhashing is here!

Keep Your State Parks Open

Governor Schwarzenegger has proposed closing 80% of California state parks, including most of those in the Bay Area. This is estimated to save $143 million out of a $24 billion deficit, or half a percent. This strikes me as a very poor decision given the miniscule effect it would have on California's finances, and the large effect it would have on California's quality of life. Furthermore, it may end up costing the state more than it saves if it decreases tax revenues from tourism. Admittedly it's a tough decision to spend $143 million on parks rather than on health insurance for poor children, but ultimately $143 million is a drop in the bucket for the latter. To put this in perspective, $143 million is $4.35 per capita after removing the unemployed. I'd much prefer higher entry fees or taxes to outright closures, or he could parole ~3000 non-violent drug offenders instead.

This site makes it easy to contact your state representatives.

Closing these state parks means that gates would be padlocked, and parking and restrooms won't be available, though it will likely still be physically possible to enter. You can find a list of all 220 here. Here are a few of my photographs from the parks they are intending on closing.

Point Lobos

Big Basin

Prairie Creek Redwoods

Henry W. Coe

Sugarloaf Ridge

Pfeiffer Big Sur

Castle Rock

Moss Beach