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Andrew Reid
Works at NIST
Attended Queen's University
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Andrew Reid

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Brilliant and hilarious comic artist Richard Thompson, creator of the "cul de sac" comic strip, and all-around hilariously insightful guy, died today of complications from Parkinson's disease.

I was a pretty big fan of his strip, and met him very briefly (i.e. long enough for him to sign whatever I was buying) at a few public events, once at the Small Press Expo in Bethesda, and at least once at a promotional event at a local independent bookstore. The one I recall was for "The Complete Cul de Sac".

The guy was amazing, and his early departure is a damn shame.
The Reuben Award-winning cartoonist died of complications from Parkinson's disease, the effects of which he had endured for eight years.
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From Mental Floss, an angle on why spam e-mails are clumsily crafted and obviously spammy.

The claim is that it's a time-management strategy for the spammers. They don't want a big haystack full of responses, with only a few needles which will actually send money, they want to go straight to the needles. By making the e-mails obvious, they deter the savvy or skeptical from engaging, and restrict responses to a smaller but more gullible subset, which is more target-rich for them.

The full article is here:
https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/WhyFromNigeria.pdf

The article does a reasonable job of quantifying the model, posed as a classification problem for the attacker, but it seems like it's still fundamentally a plausibility argument -- it does not address, for example, the fact that maintaining a high level of spammy character in the messages makes them easy to filter, which presumably means some receptive victims will never see the thing. Is this a small enough effect to justify the strategy? How would an attacker know this?

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Meanwhile, lots of people making fun of the new Trump/Pence campaign logo. I feel this is somehow related...
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Today's ride.

One of the things that makes bicycling such good exercise is that it's pretty easy to trap yourself into doing more than you intended.

Today was an example -- I started out with the idea of doing what I call the "Bethesda Trolley Loop", which is this one: http://www.mappedometer.com/?maproute=111071

But, I was keenly aware that this was the first big-deal ride I've done in many weeks, so I had some bail-out points in mind. After cruising through downtown Bethesda, it seemed clear that I was over-doing it, so I decided to take the Massachusetts Avenue bail-out and short-cut back home through northwest DC. The part of this that I remembered was that it's an easy downhill for the last bit. The part I totally failed to appreciate was that the transition from the Capitol Crescent Trail to the northwest DC bike paths is about three miles long (from miles 19 to 22, roughly, on the linked map), and is a 200-foot climb.

So much for my short cut.
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"Take the long way home." -- Supertramp
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Via Hacker News, an interesting bug that prevented an emacs client program from connecting to its parent emacs server, due to environment sanitizing in the perl executable that launches emacs.

Take-away quote: "This computer stuff is amazingly complicated. I don't know how anyone gets anything done."
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Good read - not only a good investigation but also a good writeup. Nice to see someone so thorough. On a personal note, it would never occur to me to use IRC to get help.
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Robert Farley (of the Lawyers, Guns , and Money blog) has a bit in the National Interest about the storied Avro Arrow, concluding that its cancellation was entirely reasonable, it was too late for interceptors once SAMs and integrated radar networks were on-line.

It really does still live on, and is near to my heart, I was amazed and pleased to find an exhibit dedicated to it in the departure area at YYZ recently.

It was also part of my introduction to conspiracy theories, some of my relatives were among those who at least wondered whether nefarious American interference was involved in the cancellation, which was, as Farley describes, a tectonic event in the Canadian aviation industry.

+Lawyers, Guns and Money
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Besides, who needs a polite fighter aircraft?
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Could a neuroscientist understand a microprocessor?

This has been bubbling away in my various newsfeeds for a while, and I finally got around to reading it. The answer, unsurprisingly, is that the methods of neuroscientists give rise to results which are very, very far from the readily-available engineering understanding of the system.

What I had not appreciated until I finally dove in is that the work builds on the Visual6502 (http://www.visual6502.org/JSSim/expert.html), which I have had a lot of fun with over the years.

The scheme is, they apply activity maps, spike-train analysis, and lesion studies to an operating, simulated 6502 under three behavioral conditions -- Donkey Kong, Space Invaders, and Pitfall. In each case, they are able to identify subsets of transistors in the chip which, when disabled, inhibits one behavior but not others (bottom of page 4, top of page 5, in the section "Lesion a single transistor at a time").

My guess is that the obvious cautionary conclusion applies not only to biological neural systems, but also gene expression, where isolating the "gene for X" often seem to rely on a similar combination of blunt tools and sharp logic.

Hat tip to Alex Tabarrok for an accessible summary (http://marginalrevolution.com/marginalrevolution/2016/05/68515.html)

The full paper is here (PDF link): http://biorxiv.org/content/biorxiv/early/2016/05/26/055624.full.pdf

Tagging +mos6502 in the unlikely event they haven't seen this yet.
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This is lovely. I sometimes think I should actually try to learn some Scots, or at least memorize some Burns, but have only managed a few phrases, ye ken.
 
this is by tom leonard and i can't think of many poets who have made me so happy, imagine poets making you happy. Embedded image. 6:34 PM - 19 Jul 2016. 7 Likes. Reply to @HINIONGE. Replies. niɒi. 2h2 hours ago. niɒi @eeeeeein. @HINIONGE reading it aloud was a lot of fun.
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Today's ride. It's the smaller version of the Bethesda loop, but with a small detour into Virginia at the end, which adds a bit of interest. Also, unlike last week, this one has the big "heartbreak hill" near the end, which worked out fine.

I wonder if there's some simple way to correct the elevation profiles -- there are four anomalous dips in this one, the one at the very beginning and at the very end, which are when I go over the Taft Bridge but the elevation profile goes through the valley, and one for each crossing of the Potomac, around mile 19 and again around mile 20, where the I go up and over the bridge, but the elevation profile follows the river.
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Low-pass filter? Or something a bit more hacky that looks for pairs of points with the same elevation and not too far apart that have a large area between them on the "abs(elevation(x) - base)" curve. If so, maintain the same elevation between those points. A sort of "never happened" approach.
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So apparently this is approximately the 100th anniversary of the domestication of the blueberry, although the linked article doesn't really call that out.

I have a tendency to forget just how much of humanity's environment is a product of human actions, the article is a nice demonstration of that.

Also, fresh blueberries are awesome.

h/t HN.
Frederick Coville and Elizabeth White, two strangers, domesticated the blueberry together. They valued beauty and worked to support local communities.
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On the value of documentation

Many years ago, when i was still living in Chicago, I donated my car to a local civic organization, one of those places that writes up a generous estimate of the value, which you can then write off your taxes as a charitable gift.

While we were completing the paperwork on this in the office, one of the charity's staffers took the car, ostensibly for a test drive, but in any case, had vanished by the time we were done with the i's and t's and so forth. It still had my plates on it.

I started getting parking tickets in the mail. At the time, the City of Chicago allowed you to contest parking tickets by mail, so I made a copy of the donation receipt, the counter-signed vehicle title, and a cover letter explaining in proper Asperger-syndrome detail that I was not contesting the violation, but that I was contesting my liability for the violation on the basis that it wasn't my car.

Over the course of a year or so, I got maybe twelve to fifteen of these. I eventually had a little kit set up, where when a violation notice arrived, I could just take one from pile A, one from pile B, fill in the date and sign the cover letter, and have my plea of non-liability in the mail within a few minutes.

This worked, some time after the flow of tickets slowed, I got a big fat red envelope from the city, with findings of non-liability for all of them.

The major fragility of this system, it seemed to me, was that if I had moved during the interim, the whole business would come undone. I couldn't change my address on the vehicle registration, because it wasn't mine, so presumably my successor at the address would get a bunch of irrelevant-to-him violation notices, discard them. If they ever got to me, I could contest them as before, but it's easy to imagine them becoming delinquent and going to collections before I get a chance to respond.

For the guy in this story, it sounds like something like that has happened. Hopefully he has enough of the right sort of paperwork to clear it all up eventually.
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I had a debt-collection agency bothering me for a while because the previous owner of my home phone number had them after him. But, surprisingly, after I actually called the number to contest the claims and told them I wasn't the guy, the calls stopped.
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Slightly late to this party, but I'm catching up on the often-awesome LanguageLog blog, and find myself nodding vigorously in agreement with my many experiences of "nerdview", as defined here by G. Pullum.

It's what happens when someone familiar with the ins and outs of some system allows system-specific terminology, which is reasonable to someone familiar with the details of the system's operations, to leak out to the user interface, where it's likely to baffle people who lack this context.

The "interchange level" example comes from an elevator at King's Cross station in London, which starts automatically from the Tube level, goes to another level, opens the doors, and announces that this is the "interchange level", without many clues as to whether this is in fact the level where the mainline trains are, or if there are other levels.

There are several other good examples. One that is not discussed is one that, while not exactly misinformation, nevertheless bugs me -- it's when I hear from the voice-mail bot that "calls will be answered in the order in which they are received." To the system managing the queue, this is clear, the calls came in in some order, and the queue is being operated first-in, first-out. But, beyond a vague appeal to my sense of fair play, the message doesn't actually convey any information to me. My individual call has a position in the queue, which is unknown to me, but it doesn't have an order at all, only the calls collectively in the queue have that, and that too is unkonwn to me.

I'm deeply sympathetic to both sides, actually. I've written documentation, it's hard to know how to describe things. Useful documentation is brief and clear, and so is narrowly-defined technical terminology, so the temptation to use the latter tool to achieve the former goal is considerable. I've also struggled with opaque labels in various contexts.
Arriving at the London Underground subway station deep below King's Cross railway station, the main London terminal for trains to Edinburgh using the East Coast main line. I'm lugging a heavy wheeled bag, and there are flights of ordinary stairs as well as escalators, so I take the passen
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I'm definitely with you on sympathy for both viewpoints. As a builder of systems it is difficult to think from an outsider perspective. Your mental capacity can be practically exhausted just keeping an internal model of the system that allows you to build and modify it. I think this same effect makes it hard to test one's own code. You're just too close to the problem and details of a particular solution to really come up with good test cases.

There's a kind of reverse phenomenon here where you have to decipher error reports that are given in non-nerdview often thanks to the good work of UI designers who helped construct a user-centered interface and terminology. At a minimum the users have different names for things. Android OS releases drive me a bit batty this way. The (official?) names are letters of the alphabet but sweet food names like Lollipop, Gingerbread and Ice Cream Sandwich. Internally they all have standard release numbers so you must consult a table just to figure out which version of the OS you're targeting. I can't even remember, offhand, if those names are what users will report or if their 'about this device' screens give the internal numbers. I'm similarly annoyed by Intel processor names where there are the numeric identifiers and then the code names like "Sandyhill" or whatever.

Though you're lucky if you get non-nerdview error reports. Mostly you get a version of the original message altered due to human memory or transcription error (or worse like "it didn't work" or "it crashed"). I don't put blame on the user's here -- precise and accurate reporting is not at all a natural human trait. But I might bemoan in the same was as the author. Since precise, accurate and detailing reporting is so obviously beneficial to resolving problems it's a wonder why people just don't do it.

I remember IBM's version of Unix (AIX?) where they added error code numbers to all the command-line error messages. At first I thought it rather against the culture and jarring, but I came to appreciate while most those seeking help could not give you the exact wording of an error message they would do very well at reading back the error number which was a real help in diagnosing just what had gone wrong. I think it might be because a number or letter-number code is not something our brains can pick up and transform to something else without our thinking about it. We're forced to literally repeat what we see. Hmmm, maybe getting people to read an error message backward might have the same effect.

I guess what I'm getting at is that beside it being difficult to have a user perspective, there's an incentive to use terminology that is close to an internal model to make handling errors easier. When fixing program problems I often feel like a detective trying to solve a case with as little information as possible and with unreliable witnesses. And most of the time I'm dealing with error reports from QA testers!
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So apparently Delta has noticed that thing where, if you have more than one server for a single queue, the throughput gets increased by a factor greater than the number of servers in use.

I'm eager to see this get more widely deployed, but I'm not sure "innovation" is the right description. It's a basic result of queuing theory, and arises because, with a single server, the queue is rate-controlled by the slowest transaction, but with multiple servers, you have to have multiple coincident slow transactions to stall the queue. The application of this to airport security isn't even innovative, I saw it at both Heathrow and Barcelona on my recent business trip. It's not a panacea, by any means, my security experience at Heathrow was far from optimal, but that was unrelated to queue management issues.
Delta's 'Inovation Lines' project moves travelers through TSA checkpoints u to twice as fast, reducing wait times and frustration levels.
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Found a weirdly incomplete analysis here:
http://aix1.uottawa.ca/~glamothe/mat4371/Queues.pdf

The "incomplete" part is that they don't define their notation, but assuming they are using the same scheme as Wikipedia, an M/M/1 queue has a line-up for one server, and an M/M/2 queue has one line-up for two servers. Other undefined parameters seem to be, lambda is Poisson process parameter for the arrival rate, and mu is the exponent of the exponential distribution of service times.

You can only actually compute closed forms for the average waiting time for stationary states of the system.

It seems obvious (although I confess I haven't even done this basic calculation yet) that an M/M/2 queue will outperform an M/M/1 queue with the same parameters -- the M/M/2 queue has more resources, so it had bloody well better do better (and, staying on topic, this seem to be part of what Delta has figured out -- just easing up on the filling-the-bin chokepoint already helps).

Less obvious, but as I recall still true, is that a single M/M/2 queue with arrival rate lambda outperforms two M/M/1 queues, each with half the arrival rate, assuming the same service-time distribution, where "outperforms" means has better throughput, corresponding to a lower average waiting time. I'm less sure that it's better on other metrics, like server utilization.
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Education
  • Queen's University
    Physics, 1989 - 1994
  • University of British Columbia
    Physics, 1986 - 1989
  • University of British Columbia
    Physics and Computer Science, 1982 - 1986
Basic Information
Gender
Male
Story
Tagline
Clever. Maybe clever enough.
Introduction
I studied computer science and physics at UBC, and have never really let go of either. I read a lot. Geeky, but not in a debilitating way.
Bragging rights
I know how much wood a woodchuck would chuck, but I'm not telling.
Work
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Scientific computing
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  • NIST
    Scientific computing, present
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Washington DC
Previously
Canada - Calgary - Vancouver - Chicago