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Thomas Colthurst
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Attended MIT
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Thomas Colthurst

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Like The Beatles in 1966 or Western painting in the 1870s, neural networks have moved beyond mastery and are now entering their psychedelic phase.

And I never thought I would have to say this in a post about machine learning, but:  WARNING!  SOME OF THESE PICTURES FEATURE EYEBALLS EVERYWHERE AND MAY CAUSE NIGHTMARES.
 
Artificial Neural Networks have spurred remarkable recent progress in image classification and speech recognition. But even though these are very useful tools based on well-known mathematical methods, we actually understand surprisingly little of why certain models work and others don’t.

Over on the Google Research blog, we take a look at some simple techniques for peeking inside these networks, yielding a qualitative sense of the level of abstraction that particular layers of neural networks have achieved in their understanding of images. This helps us visualize how neural networks are able to carry out difficult classification tasks, improve network architecture, and check what the network has learned during training. 

It also makes us wonder whether neural networks could become a tool for artists—a new way to remix visual concepts—or perhaps even shed a little light on the roots of the creative process in general.
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The answer involves the average wind speed velocity of an unladen seed pod, the controversial field of plant computation, the infrared properties of foliage shade, chemical warfare in plants, and of course, Ent fan fiction.

Really.
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Totally fascinating. Thanks. 
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Surprised by the recent UK election results?  You wouldn't have been if you paid attention to the prediction markets and not the polls.  (And that includes models based on polls, such as fivethtiryeight's.)
The polling fiasco in the 2015 UK general election is just the latest in a string of high-profile failures over the last few months. This contrasts with the good performance of prediction markets, ...
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The polls definitely failed this one, but I wouldn't say 66% compared to 80% on the conservatives getting more seats accounts for even half of what the polls got wrong.

Of course it's hard to compare when everyone is predicting different things... Chance of conservative government... Plurality of conservative seats... And all you get to measure at the end is the number of total seats won (which the polls definitely got wrong, but I don't see any predictions for in the market).
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Nice profile of my old talk.bizarre pal Jeff Vogel.  Lots of good insights into game design, if you are into that.  It neglects to mention that Jeff also wrote an extremely funny book, The Poo Bomb, which I recommend to all new parents.  (Though come to think of it, it also works as a highly effective method of birth control for non-parents.) 
Jeff Vogel has created a prolific, independent game development success story without leaving his house. He tells us how it's done.
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Love the McCartney analogy :)
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About Me. My Photo: Name: Greg Mankiw: Location: United States. I am a professor and chairman of the economics department at Harvard University, where I teach introductory economics (ec 10). I use this blog to keep in touch with my current and former students. Teachers and students at other ...
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"Observing Ultra-High Energy Cosmic Rays with Smartphones" by Daniel Whiteson et al.

Abstract:  We propose a novel approach for observing cosmic rays at ultra-high energy (> 10^18 eV) by repurposing the existing network of smartphones as a ground detector array.  Extensive air showers generated by cosmic rays produce muons and high-energy photons, which can be detected by the CMOS sensors of smartphone cameras.  The small size and low efficiency of each sensor is compensated by the large number of active phones.  We show that if user adoption targets are met, such a network will have significant observing power at the highest energies.

You can sign up for the app at http://crayfis.ps.uci.edu/ and there is some popular press coverage at http://arstechnica.com/science/2014/10/cosmic-ray-particle-shower-theres-an-app-for-that/.  The app only actually runs when your phone is charging and not being used.  HT to Marginal Revolution.
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Thomas Colthurst

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For every dollar we spend on Medicaid, what is the value of the benefits that the recipient gets?

A new paper uses the Oregon Health Insurance Experiment (see https://plus.google.com/+ThomasColthurst/posts/jRcHqLUdonb and https://plus.google.com/+ThomasColthurst/posts/4hshmyRZHri for my previous posts on the experiment) to answer that question.  It's called, naturally enough, "The Value of Medicaid:  Interpreting Results from the Oregon Health Insurance Experiment".

The answer in the paper's abstract is "$0.2 to $0.4", but they also do a sensitivity analysis using a variety of "reasonable" assumptions (their scare quotes, not mine) that gives a range from $0.15 to $0.85.  The authors (Amy Finkelstein, Nathaniel Hendren, and Erzo Luttmer) note that these estimates are in line with previous measurements of how much Medicaid recipients would be willing to pay for their benefits, which give values from $0.3 to $0.5.

The astute reader will notice that all of these amounts are less than $1.

HT to Marginal Revolution.
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Thomas Colthurst's profile photoMeg Muckenhoupt's profile photo
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It's not about making other people happy. It's about preventing catastrophic costs from other peoples' illness (assuming you feel the need to keep people alive when they arrive at the hospital.) In countries that are not the US, care like prenatal check-ups and diabetes treatment improves measurable outcomes like infant mortality, rate of premature birth, and rate of disability. In the US, that doesn't work as well. The theory I've heard is that it's because US medical care doesn't undo the effects of poverty (stress, bad diet, lack of dental care, etc.), while in other countries where life is more secure for low-income residents, consistent medical care can make a difference. But I haven't studied this topic in depth. 
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This article attempts to critique effective altruism as being insufficiently radical:

"As practiced by GiveWell, Singer-style philanthropy is palliative, an attempt to reduce suffering that leaves untouched the question of what generated the suffering in the first place, and what long-term solutions there might be to end its continual reproduction. It offers nets to help individual Africans avoid malaria while ignoring the structural, political, and economic reasons malaria is rampant."

The author goes on to recommend that we all instead fund leftwing social movements that fight against racism, capitalism, etc.

This all betrays an incredibly superficial understanding of what GiveWell is all about.  GiveWell's fundamental commitment isn't to funding palliatives, or to ignoring social contexts, it is to empiricism.   They would be more than happy to fund a long term solution to malaria if there was hard evidence that such a solution was cost effective.

How do I know this?  Because GiveWell has explicitly evaluated similar eradication campaigns for polio and Guinea worms.  (See http://www.givewell.org/international/technical/programs/disease-eradication for details.)  GiveWell is also perfectly willing to direct funding towards advocacy organizations; for example Deworm the World is a current top charity that lobbies governments to spend more on deworming.

Now, to be fair, you might argue that insisting on empirical evidence of effectiveness does bias GiveWell and the effective altruism movement in general towards low complexity interventions, and that low complexity interventions are unlikely to effect structural change.  That would be an interesting argument, but it is not one that this article makes.

And please be aware of the counterargument:  years of experience by GiveWell, Poverity Action Lab, and other researchers has established that even low complexity interventions are extremely hard to evaluate a priori.  Knowing what problem an intervention is trying to address can give you an upper bound on its effectiveness, but that's about it.  We should all be skeptical of all our intuitions, but especially our intuitions about (1) being able to identify root causes or (2) being able to predict what interventions will cost effectively address those root causes.

TL;DR:  Article radically misunderstands what effective altruism is about by focusing on one of GiveWell's top rated charities, instead of the process by which that charity was found, or why indeed that empirical process is necessary to begin with.

Hat tip to +Lori Kenschaft
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I'd summarize the moral world envisioned by the OP somewhat differently, by way of analogy:

Suppose the biggest guy in class offers me $5 a day to help him with his homework. Sweet! Not only will this help me save up for that really rad Casio keyboard I've wanted, but being on good terms with the big guy can only help if small-time bullies come around.

Later, I realize that there's two kids in the class who are constantly going hungry at lunch; they never seem to have lunch money. Well, certainly their hunger is more important than my MIDI mastery, so I take 40% of my homework income, and buy them each a granola bar each day.

But then, I start to hear rumors, unsubstantiated, but credible, that the big guy is actually strong arming these kids for their lunch money each day, and that's what he's using, at least in part, to pay me to tutor him.

What I should do next becomes messy. But paying a friend to escort the two hungry kids to school tomorrow, just to see what happens, doesn't strike me as obviously morally deficient compared to just continuing to buy granola bars.
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I have a new blog.  This is its first post.  It's all about extending proportional voting to Presidential elections, but it is much more fun than that sounds, honest.
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At least initially, yes.
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Key quote:  """Asked to explain the high-sugar, high-salt diet that has somehow enabled him to remain seemingly healthy, Buffett replies: “I checked the actuarial tables, and the lowest death rate is among six-year-olds. So I decided to eat like a six-year-old.” The octogenarian adds, “It’s the safest course I can take.” """

HT to Reddit.
The world's most successful investor stays youthful by drinking at least five Cokes a day. Turns out, the Berkshire Hathaway CEO's bizarre diet is highly strategic.
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In countries where there isn't as large a disparity in access to health care, nutrition and so on between people with different income levels, there isn't as strong a correlation. 
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In case any of you need some cheering up on this snow day.
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Fish N's profile photoTom Heller's profile photo
 
Perfect! An astonishing insight into my universe 😳
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In the words of the Onion's AV club, "This Firefly fan film is surprisingly great."  All different characters than Firefly, but set in the same universe with the same aesthetics.
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