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More on the Deutschlandtakt

The Deutschlandtakt plans are out now. They cover investment through 2040, but even beforehand, there’s a plan for something like a national integrated timetable by 2030, with trains connecting the major cities every 30 minutes rather than hourly. But there are still oddities that are worth discussing, especially in the context of what Germans think […]

via Pedestrian Observations July 1, 2020

How do cars fare in crash tests they're not specifically optimized for?

Any time you have a benchmark that gets taken seriously, some people will start gaming the benchmark. Some famous examples in computing are the CPU benchmark specfp and video game benchmarks. With specfp, Sun managed to increase its score on 179.art (a sub-benchmark of specfp) by 12x with a compiler tweak that essentially re-wrote the benchmark kernel, which increased the Sun UltraSPARC’s overall specfp score by 20%. At times, GPU vendors have added specialized benchmark-detecting code to their…

via Posts on Dan Luu June 30, 2020

The French Way of Building Rapid Transit

It’s been a while since I last wrote this series, where I covered the American, Soviet, and British traditions of building urban rail. I’d like to return by focusing attention on the French tradition, which has been influential not just within France itself but also to some extent former French colonies, especially Quebec. An issue […]

via Pedestrian Observations June 29, 2020

Modernizing Rail Unconference

On Sunday the 12th of July, a few of us public transit activists are going to hold a conference online called Modernizing Rail, focusing on better service and integration in the Northeastern United States. Our keynote speaker will be Vukan Vuchic, the Serbian-American UPenn transportation professor who imported German rail modernization schemas from the 1970s, […]

via Pedestrian Observations June 25, 2020

Construction Costs, Inflation, and Developing Countries

As our construction cost project moves forward, we are expanding our database to be as complete as possible. My original dataset is mostly in developed countries, but does have decent coverage in developing ones other than China. However, decent and good are two very different things, and expanding coverage showcases some problems. These are all […]

via Pedestrian Observations June 23, 2020

Quick note on the name of this blog

When I was 21 a friend introduced me to a volume of poems by the 14th-century Persian poet Hafiz, translated by Daniel Ladinsky. I loved them, and eventually named this blog for one of my favorite ones. At some point I read more and found that Ladinsky’s “translations” were more like riffs on themes in […]

via The whole sky June 21, 2020

On scruffy spaces

Before I had children, I liked to think about how I would decorate their rooms. I collected Pinterest boards full of images like this, full of colorful, whimsical objects. Now that I’ve actually tried it, I see more of the backstory behind these photos. Know who assembled, maintained, and photographed these rooms? Adults. What kind […]

via The whole sky June 21, 2020

Transportation Renaissance

Ada Palmer posts rarely, but when she does, it’s always worth reading. She alternates between writing about her science fiction and writing about academic history; her most recent post is the latter, covering the historiography of the Renaissance. She notes that the idea of a three-age system, in which great Ancient knowledge was lost in […]

via Pedestrian Observations June 21, 2020

My weekly review habit

how it works • example topics • compounding improvements • what I’ve gotten out of it • tips

via benkuhn.net June 21, 2020

My personal avocado toast recipe

I don’t like to make a big thing out of identifying with my generation, but millenials have one things right: avocado toast is the perfect breakfast food. This is my very simple and quick recipe, which, yes, I did invent. Recipe time: ~5 minutes Yields: 4 slices Ingredients: 4 slices of bread for toasting (I […]

via Holly Elmore June 10, 2020

Don’t fear regret

It is normal and healthy to have regrets. I have lived in mortal fear of regrets most of my life. And guess what? I regret it. There’s no getting around them– just listen to your feelings and learn from them. “I’m not okay, and that’s okay” is a popular saying for dealing with grief. We […]

via Holly Elmore June 10, 2020

DIY server-only analytics with almost no code

(Attention conservation notice: only useful if you have a static site that you’d like to remove the Javascript from. I don’t normally find “how to do X with Blub and Glug” tech posts very useful, but this one took me a while to figure out how to do simply, and I’m hoping it will help other folks with static sites eliminate their Google Analytics dependency.) I have the following website problem:

via benkuhn.net June 10, 2020

Wireless is a trap

Over and over again, I’ve seen people fix some wireless-related problem and go “wow, I had no idea how much better this could be!” • Wireless protocols often silently operate in an extremely degraded state that makes them substantially worse than wired equivalents.

via benkuhn.net June 7, 2020

A simple way to get more value from tracing

A lot of people seem to think that distributed tracing isn't useful, or at least not without extreme effort that isn't worth it for companies smaller than FB. For example, here are a couple of public conversations that sound like a number of private conversations I've had. Sure, there's value somewhere, but it costs too much to unlock. I think this overestimates how much work it is to get a lot of value from tracing. At Twitter, Rebecca Isaacs was able to lay out a vision for how…

via Posts on Dan Luu May 31, 2020

A simple way to get more value from metrics

We spent one day1 building a system that immediately found a mid 7 figure optimization (which ended up shipping). In the first year, we shipped mid 8 figures per year worth of cost savings as a result. The key feature this system introduces is the ability to query metrics data across all hosts and all services and over any period of time (since inception), so we've called it LongTermMetrics (LTM) internally since I like boring, descriptive, names. This got started when I was looking for a st…

via Posts on Dan Luu May 30, 2020

Embrace mediocre tastes, true happiness

The plain fact is that there are no obvious moral consequences to how people entertain themselves in their leisure time. The conviction that artists and connoisseurs are morally advanced is a cognitive illusion, arising from the fact that our circuitry for morality is cross-wired for with our circuitry for status. — Steven Pinker, The Blank Slate […]

via Holly Elmore May 24, 2020

Learning to build conviction

fast vs slow feedback • modeling people vs. modeling the problem • mentors vs. mistakes • why you should do the hard thing now

via benkuhn.net May 16, 2020

College advice for people who are exactly like me

It’s college decision season! To celebrate, I’ve been thinking about what I would have told myself in 2011 when I was deciding where to attend.

via benkuhn.net April 12, 2020

Finding home in the time of coronavirus

Disclaimer: I’m going to say this once. Obviously, I am not happy about the coronavirus’s threat to public health or the economic toll it’s taking. I do not think the existence of this pandemic is good. Just so happens that social distancing and remote work suits me. I am truly an introvert, and this whole […]

via Holly Elmore March 31, 2020

Have it all: take your spouse’s name socially

When you get married, you are creating a family. One way to reinforce that is to have the same name. But whose name do you pick? Do you hyphenate? Do you not hyphenate, and never have a simple time filling out a form again (like my friends the Rabideau Childerses)? Do you make a new […]

via Holly Elmore March 31, 2020

Several grumpy opinions about remote work at Tailscale

As a "fully remote work" company, we had to make some choices about the technologies we use to work together and stay in touch. We decided early on - about the time we realized all three cofounders live in different cities - that we were going to go all-in on remote work, at least for engineering, which for now is almost all our work. As several people have pointed out before, fully remote is generally more stable than partly remote. In a partially remote team, the remote workers seem to …

via apenwarr March 11, 2020

How (some) good corporate engineering blogs are written

I've been comparing notes with people who run corporate engineering blogs and one thing that I think is curious is that it's pretty common for my personal blog to get more traffic than the entire corp eng blog for a company with a nine to ten figure valuation and it's not uncommon for my blog to get an order of magnitude more traffic. I think this is odd because tech companies in that class often have hundreds to thousands of employees. They're overwhelmingly likely to be better …

via Posts on Dan Luu March 11, 2020

The growth of command line options, 1979-Present

My hobby: opening up McIlroy’s UNIX philosophy on one monitor while reading manpages on the other. The first of McIlroy's dicta is often paraphrased as "do one thing and do it well", which is shortened from "Make each program do one thing well. To do a new job, build afresh rather than complicate old programs by adding new 'features.'" McIlroy's example of this dictum is: Surprising to outsiders is the fact that UNIX compilers produce no listings: printing can be do…

via Posts on Dan Luu March 3, 2020

It's ok to feed stray cats

Before we had kids, Jeff and I fostered a couple of cats. One had feline AIDS and was very skinny. Despite our frugal grocery budget of the time, I put olive oil on her food, determined to get her healthier. I knew that stray cats were not a top global priority, and that this wasn’t even the best way of helping stray cats, but it was what I wanted to do.. . . . .The bike path near where I live has a lot of broken glass on the ground nearby. My family likes to go barefoot in the summer, and a lo…

via Giving Gladly January 27, 2020

Hedonic asymmetries

Creating really good outcomes for humanity seems hard. We get bored. If we don’t get bored, we still don’t like the idea of joy without variety. And joyful experiences only seems good if they are real and meaningful (in some sense we can’t easily pin down). And so on. On the flip side, creating really … More Hedonic asymmetries

via The sideways view January 26, 2020

Moral public goods

Suppose that a kingdom contains a million peasants and a thousand nobles, and: Each noble makes as much as 10,000 peasants put together, such that collectively the nobles get 90% of the income. Each noble cares about as much about themselves as they do about all peasants put together. Each person’s welfare is logarithmic in … More Moral public goods

via The sideways view January 26, 2020

git-subtrac: all your git submodules in one place

Long ago, I wrote git-subtree to work around some of my annoyances with git submodules. I've learned a lot since then, and the development ecosystem has improved a lot (shell scripts are no longer the best way to manipulate git repos? Whoa!). Thus, I bring you: git-subtrac. It's a bit like git-subtree, except it uses real git submodules. The difference from plain submodules is that, like git-subtree, it encourages you to put all the contents from all your submodules into your superproject r…

via apenwarr November 24, 2019

Pieces of time

My friend used to have two ‘days’ each day, with a nap between—in the afternoon, he would get up and plan his day with optimism, whatever happened a few hours before washed away. Another friend recently suggested to me thinking … Continue reading →

via Meteuphoric November 11, 2019

Ethical experimentation

I suggested experimenting with different settings on personal characteristics that aren’t obviously good or bad. For instance, trying out being more or less perfectionistic for a day. A particular variety of this that interests me is experimentation with different ethical … Continue reading →

via Meteuphoric November 10, 2019

For the metaphors

I make use of a lot of analogies, for instance ‘like dancing’ and ‘the ice skating thing’ are particular phenomena I often think about, and I get value from thinking about meta-ethics as if it were romance, or saving the … Continue reading →

via Meteuphoric November 8, 2019

Self policing for self doubt

Sometimes it seems consequentially correct to do things that would also be good for you, if you were selfish. For instance, to save your money instead of giving it away this year, or to get yourself a really nice house … Continue reading →

via Meteuphoric November 7, 2019

Wild animal welfare in Hans Christian Andersen

Continuing the theme of wild animal suffering in children’s lit… Hans Christian Andersen’s stories involve a lot of suffering of both human and animal varieties. “The Ugly Duckling” takes a brief detour from describing the duckling’s repeated social humiliations to describe being a waterfowl in winter: The winter grew cold – so bitterly cold that […]

via The whole sky November 7, 2019

Personal quality experimentation

Different people seem to have different strategies, which they use systematically across different parts of their lives, and that we recognize and talk about. For instance people vary on: Spontaneity Inclination toward explicit calculations Tendency to go meta Skepticism Optimism … Continue reading →

via Meteuphoric November 6, 2019

Prediction markets for internet points?

Using real money in prediction markets is all-but-illegal, and dealing with payments is a pain. But using fake money in prediction markets seems tricky, because by default players have no skin in the game. Here’s a simple proposal that I think might work reasonably well without being too hard to try: Create a service that … More Prediction markets for internet points?

via The sideways view October 27, 2019

What do executives do, anyway?

An executive with 8,000 indirect reports and 2000 hours of work in a year can afford to spend, at most, 15 minutes per year per person in their reporting hierarchy... even if they work on nothing else. That job seems impossible. How can anyone make any important decision in a company that large? They will always be the least informed person in the room, no matter what the topic. If you know me, you know I've been asking myself this question for a long time. Luckily, someone sent me a link to a …

via apenwarr September 29, 2019

Taxing investment income is complicated

How should a state tax investment income if it wants to maximize its citizens’ welfare? This sounds like a simple question but I find it surprisingly hard to think about. Here are some of the positions I’ve moved through over the last few years: Taxing investment has distortionary effects, but we should have non-zero investment … More Taxing investment income is complicated

via The sideways view September 22, 2019

Reframing the evolutionary benefit of sex

From the perspective of an organism trying to propagate its genes, sex is like a trade: I’ll put half of your DNA in my offspring if you put half of my DNA in yours. I still pass one copy of my genes onto the next generation per unit of investment in children, so it’s a … More Reframing the evolutionary benefit of sex

via The sideways view September 14, 2019

Bear store

A preschool game that’s been particularly popular and versatile with my kids. Materials: Pennies Collection of counting bears or any other small objects One person is the storekeeper and sets out the bears in any way they want. The other people are customers and bring some pennies. The storekeeper sells the bears to the customers. […]

via The whole sky September 9, 2019

Graveyard Shift at Dawn Dance

I would say I’m alllmost recovered from the all-nighter I pulled this weekend calling the graveyard shift (4AM–7AM)—but heck, what a blast! Here’s the program I called (most of these walked through minimally or not at all): 50/50 — Bob Isaacs Fiddler’s Fling — Cary Ravitz (Will Mentor var.) Maliza’s Magical Mystery Motion — Cary Ravitz Rollin’ to the Grey Eagle — Hank Morris Read Between the Lines — Bob Isaacs The Young Adult Rose — David Kaynor Treasure of the Soda Bar — Maia McCormick Cheat Lake Twir…

via Maia Calls Dances September 4, 2019

Absolute scale corrupts absolutely

The Internet has gotten too big. Growing up, I, like many computery people of my generation, was an idealist. I believed that better, faster communication would be an unmitigated improvement to society. "World peace through better communication," I said to an older co-worker, once, as the millenium was coming to an end. "If people could just understand each others' points of view, there would be no reason for them to fight. Government propaganda will never work if citizens of two w…

via apenwarr August 19, 2019

Traces

At naptime Anna listens to recordings of novels recorded by Jeff’s grandmother. It is the main way she will know Winnie, as it is the main way I have ever known Winnie. Some of the recordings are missing parts, and Suzie often fills in the first few sentences, her cadence echoing the distinctive pattern of […]

via The whole sky August 18, 2019

Reflections on My First Techno Contra

Last weekend, I called my first techno contra (as part of a double dance at CDNY to celebrate the wedding of two of our lovely dancing humans 😍). It turns out, to no one’s surprise, that calling techno is a fair bit different from calling a regular evening dance. Here are my reflections on calling my first techno (including a bunch of great advice from folks on SharedWeight’s Callers’ Listserv). + If you can, listen to the tracks in advance! I worked with DJ Flourish (Mark Moore) from Philly—he’…

via Maia Calls Dances April 7, 2019

Programmer migration patterns

I made a little flow chart of mainstream programming languages and how programmers seem to move from one to another. There's a more common kind of chart, which shows how the languages themselves evolved. I didn't want to show the point of view of language inventors, but rather language users, and see what came out. It looks similar, but not quite the same. If you started out in language A, this shows which language(s) you most likely jumped to next. According to me. Which is not very scie…

via apenwarr March 18, 2019

You have more than one goal, and that's fine

When people come to an effective altruism event for the first time, the conversation often turns to projects they’re pursuing or charities they donate to. They often have a sense of nervousness around this, a feeling that the harsh light of cost-effectiveness is about to be turned on everything they do. To be fair, this is a reasonable thing to be apprehensive about, because many youngish people in EA do in fact have this idea that everything in life should be governed by cost-effectiveness. I&…

via Giving Gladly February 19, 2019

Improve Your Community With This One Weird Trick!

Hey experienced contradancers! Have you been looking for a new way to contribute to your dance community? Here’s one that I’ve been trying. It’s really small, and has the potential to make a really big impact on the quality of our dances, especially as more and more of us get on board with it. Ready? Here it is: Be quiet when the caller starts talking, and don’t talk through the walkthrough. That’s it. Really. If you want to go one step further, you can be the person who gently reminds people to …

via Maia Calls Dances January 31, 2019

Words Don't Help Beginners

I’ve been contradancing for over eight years, and can jump into even the most complex and falling-apart of contras and still have some idea of what’s going on. But last summer at English-Scottish-Contra Week at Pinewoods, I tried Scottish Country Dance for the first time and I had an experience I haven’t had for quite a while: I was completely at sea in a set dance. Scottish isn’t too different from contra and English, and I got along okay when I had a walkthrough. (Not great, mind you, but I ma…

via Maia Calls Dances January 21, 2019

No one is a statistic

I’m late to the party, but I've been thinking about the documentary “The Life Equation” about how people use data to decide make life-and-death decisions. The central example is a woman named Crecencia, a mother of seven who lives in rural Guatemala and has cervical cancer. The doctor treating her knows that screening other women for cancer is more cost-effective than treating this woman, and that the community doesn’t have enough money to fully fund both. The filmmaker writes: “Crecencia’s…

via Giving Gladly October 10, 2018

On Finding Purpose

We’re often taught about the importance of “finding your purpose” as you set out into the world and choose your pathway forward. The words change–sometimes it’s ‘purpose’, but you might also find your ‘bliss’, your ‘passion’, your ‘voice’, your ‘career’, or your ‘calling’–but the narrative remains the same. Whatever it is, you’ve gotta find it. And … Continue reading On Finding Purpose → The post On Finding Purpose appeared first on Hollis Easter .

via Hollis Easter April 13, 2018

XLR Mic Mute Switch with LEDs – Proof of Concept

Purpose I play music on stage, and that usually means using amplification (PA) systems. The bands I play with (Frost and Fire, The Turning Stile+, and others) typically have a bunch of musicians playing a host of instruments, each with their own microphones. Consequently, we need a lot of mic mute switches. The enemy of … Continue reading XLR Mic Mute Switch with LEDs – Proof of Concept → The post XLR Mic Mute Switch with LEDs – Proof of Concept appeared first on Hollis Easter .

via Hollis Easter September 30, 2017

How to Test Thermostat/Thermal Fuse in Kitchen Tools

How to test thermostat and thermal fuse units on kitchen appliances (espresso machine, coffee maker, rice cooker, pressure cooker) with a multimeter. The post How to Test Thermostat/Thermal Fuse in Kitchen Tools appeared first on Hollis Easter .

via Hollis Easter September 14, 2017

Use Up That Zucchini – Googoots / Cucuzza Recipe

Delicious crispy caramelized zucchini with garlic, basil, mint, red wine vinegar, and olive oil. Easily scales up to use all the zucchini in the house, and it's quick! Googootz! The post Use Up That Zucchini – Googoots / Cucuzza Recipe appeared first on Hollis Easter .

via Hollis Easter August 27, 2017

Hotline Memes

Jennifer Battle asked the National Association of Crisis Organization Directors’ mailing list for some uplifting hotline memes to use in training, since there didn’t seem to be that many available. Here are my first responses. (please feel free to use these if you like)   The post Hotline Memes appeared first on Hollis Easter .

via Hollis Easter May 24, 2017

Two standard donations and one new one

Here are three places Jeff and I are donating this year. The first two are similar to what we’ve been doing for years, and the third represents a change.Direct workJeff and I want to support work that directly makes the world a better place. (Some arguments against falling into a “meta trap” here.) As usual for us, this year we’ve given just over half our donations to direct work. We made these donations to the Against Malaria Foundation, one of GiveWell’s top picks, except for small amounts th…

via Giving Gladly December 30, 2016

Practical steps for self-care

Last week the Boston Effective Altruism group had a discussion on self-care for altruists. I've written about the topic before, but I wanted to share some of the more practical advice people had. Think beyond day-to-day choicesSelf-care isn’t just short-term decisions like whether to make time for yoga tonight. It’s larger life decisions too, like what job to take, where to live, how to budget money, and how to make time for partners, friends, and family.For me, having children was self-car…

via Giving Gladly June 15, 2016

An Interaction or Not? Understanding a Few ML Algorithms via an Example with No Evidence Either Way

My latest blog post helps to explain a few statistical/ML models by whether they learn an interaction in a toy example Since Github Pages is way nicer than Blogger, I'm writing over there at http://davidchudzicki.com now. To keep old posts alive, these pages at http://blog.davidchudzicki.com will remain as is.

via David Chudzicki's Blog March 4, 2015

Moved

I've moved here.

via David Chudzicki's Blog June 2, 2014

dithering

I was converting a PNG (which represented partials sums of the Weierstrass elliptic function) to a GIF and was confused about why the PNG looked fine at low resolution but the GIF looked bad. Then I learned that GIFs can only use 256 colors and we have to do something to map the many colors to the fewer colors. We could just use the closest available color in the new set of colors, but that results in sharp jumps and "color banding" where the colors change. So instead we use (and Image…

via David Chudzicki's Blog January 21, 2014

Interactive Lissijous Curves in d3

On a visit to San Francisco's Exploratorium, I saw an oscilloscope they had making Lissijous curves. So I decided to make a version in d3: You can play with it (and see the code) here

via David Chudzicki's Blog January 21, 2014

A Bayesian Model for a Function Increasing by Chi-Squared Jumps (in Stan)

This post will describe a way I came up with of fitting a function that's constrained to be increasing, using Stan. If you want practical help, standard statistical approaches, or expert research, this isn't the place for you (look up “isotonic regression” or “Bayesian isotonic regression” or David Dunson, whose work Andrew Gelman pointed me to). This is the place for you if you want to read about how I thought about setting up a model, implemented the model in Stan, and created graphic…

via David Chudzicki's Blog October 17, 2013

via openring