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External filters

We're often really unsure how our abilities and ideas stand compared to others. We have a biased perspective, seeing things from the inside, and we have limited exposure to others. We're used to thinking of "gatekeepers" as people who stand in your way, keeping you from reaching you goals, but they can also serve a valuable role in letting you know how good your chances are and keeping you from wasting your time.

Let's say you want to do a PhD in math. You love the subject, you'd like to make a career out of it, and you apply to grad schools. If a school wants you, though, not only will they admit you but they'll arrange some combination of teaching and/or stipend. If they admit you but want you to pay tuition, that means they don't really expect you to do well there. So a common rule for math and similar PhDs is that you shouldn't do one unless they're offering you full funding.

Or let's say you slip on the ice in a grocery store parking lot, and want to sue. This kind of personal injury case is typically arranged with a contingent fee, where your lawyer only gets money if you win. If, after talking to various lawyers, they're only willing to take the case as self-pay, that's telling you that they don't think your case is very likely to win, and you should probably drop it.

Other examples:

  • After shopping your proposal around with an agent, do you get offered a book deal?
  • Can you get venture capital to fund your startup?
  • Can you get into a top-twelve philosophy PhD program?

You do need to keep in mind what is customary in different fields, though. If you're writing a kind of book where no one gets advances, then you can't take failure to get an advance as meaning much about you, though it does tell you things about the market for this kind of book. If you have an idea for a company that might need two employees and make $1M/year you won't get venture capital funding because they look for companies that will grow much larger than that, so failure to raise funds from them isn't a negative signal. [1]

(It's also possible for professional evaluators to get things wrong, and maybe you know something they don't. I would expect this most in situations where the evaluators' incentives and yours are not well aligned, where evaluators don't have the information to see how their decisions pan out, and where the market is too small for evaluators to have much practice.)


[1] Well, it would be a negative signal if you tried to raise money from them without realizing that this wasn't the sort of thing they're interested in funding. Though not a very strong signal, since "understands how VC works" is nearly entirely unrelated to what would make your small business successful or not.

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Shortcuts in Emacs

When I chose a text editor, nearly fifteen years ago, I chose emacs because I liked the idea of using something that was deeply customizable. While I didn't intend to start using that customization immediately, it seemed to me like it would be much more future-proof to learn something flexible. I've never actually used this very much, but a couple weeks ago I wrote a new mode for the first time, so I thought I'd write that up.

I keep my calendar as an html table, and every so often I go over it to move activities that have happened to the past. One could automate this completely, but I I like having an opportunity to review things and make fixes. So about five years ago I wrote a little function: more...

Sanders and Tax Brackets

Our tax brackets are kind of complicated, so I was surprised to see Bernie Sanders' health care proposal saying simply:

Under this plan the marginal income tax rate would be:
  • 37 percent on income between $250,000 and $500,000.
  • 43 percent on income between $500,000 and $2 million.
  • 48 percent on income between $2 million and $10 million.
  • 52 percent on income above $10 million.
To see why this is weird, let's look at our current tax brackets. Here's the amount of money you have to earn [1] before the government will start taxing you at the current highest rate, 39.6%:
Single$413,200
Married filing jointly$464,850
Married filing separately$232,425
One of these sticks out: the limit for married people filing separately is far lower than the other three. In fact, it's exactly half the threshold for married people filing jointly. What are these categories, though? In the US married people typically file one joint tax return. If you want you're allowed to file separately, one tax return each. To avoid rich people changing their filing to pay taxes at a lower rate, we shift the tax brackets higher for people filing separately.

By getting rid of this, Sanders does a few things: more...

Tiny House Movement

Houses keep getting bigger and bigger, and house prices keep going up and up. What if we went the other way, and made very small houses? The median house in Somerville sells for $500k, but you can build a very nice tiny house for less than $50k. Why go into debt for 30 years if you can build or buy a well-designed house for half what your down payment would be on an existing one?

The first problem is land. Houses in Somerville are expensive because the land is expensive: the land is typically [1] worth more than the building on it. Specifically, for the median 1, 2, or 3 family Somerville house, 55% of the value is land and only 45% is the building:

So if your land costs $350k and your structure is worth $300k, then getting your structure down to $50k or even $0 is not going to bring the total cost below $350k. Plus this area is already built up, so you can't just choose to buy a plot without the house on it and get it cheaper.

Tiny houses don't need much land, though, and existing plots generally have extra space, so can we put the houses next to other houses? There are a few tiny houses in Somerville sharing plots with larger houses:


29 Hamilton (312 sqft) more...

Bean Pasta Ratios

Bean pasta is a thing, and it tastes enough like wheat pasta that I'm pretty happy to eat it. The main reason to eat it over regular pasta is that it more protein, but it doesn't taste quite as good and costs about 2.5x as much [1] so I wouldn't want to eat just that. If I mix it with wheat pasta, though, what is the right ratio?

To make things simpler, imagine that we're relying on pasta for all our calories and protein, and it's just these two being combined. [2] Dietary requirements vary between people a lot, but standard recommendations are something like 2000 calories and 50g of protein.

On ounce of wheat pasta is 3.5g of protein and 100 calories, while bean pasta is 12.5g and 90 calories. So we want:

   3.5g x w + 12.5g x b = 50g
   100C x w + 90C x b = 2000C
This gives us: [3]
   w = 21.9oz
   b = -2.13oz
That clearly doesn't work; I don't know how to eat -2.13 ounces of anything. Why are we getting this weird result? To get 2000 calories from wheat pasta you need to eat 20 ounces, which would get you 70g of protein. So you can get enough protein with ordinary pasta alone... really?

The problem is we're treating protein as a homogenous thing, when actually it's a big bag of things. more...

Tempo Meter

How's our tempo? It looks like the dancers are rushing a bit, maybe? Is this too fast, or does it just feel fast?
Over years of playing for dances I've built up a sense of how fast the music should go. If I'm playing a rhythm I'm fully comfortable with and stamping my foot I can hold down a nice even 116-118. If I'm winding through a challenging melody or otherwise distracted, though, my sense can get off, and I might end up at 108 or 128, both of which are pretty hard to dance to. Playing with other people can help here, as we're rarely all having tempo trouble at the same time, but disagreements are painful and potentially tense.

Several years ago it seemed to me that it would work well to have a box to show you how fast you were playing. The idea is you'd leave it one the floor in front of the band, and you could just look over at it if you were curious what tempo you were at. Well, the future is here:

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