What is a sprint?

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In October we're hosting our first 'code sprint'! What is that?

A code sprint is a type of hackathon, in which efforts are focused around a small number of open source projects. They are related to, but not really the same as, sprints in the Scrum software development framework. They are non-competitive — the only goal is to improve the software in question, whether it's adding functionality, fixing bugs, writing tests, improving documentation, or doing any of the other countless things that good software needs. 

On 13 and 14 October, we'll be hacking on 3 projects:

  • Devito: a high-level finite difference library for Python. Devito featured in three Geophysical Tutorials at the end of 2017 and beginning of 2018 (see Witte et al. for Part 3). The project needs help with code, tests, model examples, and documentation. There will be core devs from the project at the sprint. GitHub repo is here.
  • Bruges: a simple collection of Python functions representing basic geophysical equations. We built this library back in 2015, and have been chipping away ever since. It needs more equations, better docs, and better tests — and the project is basic enough for anyone to contribute to it, even a total Python newbie. GitHub repo is here.
  • G3.js: a JavaScript wrapper for D3.js, a popular plotting toolkit for web developers. When we tried to adapt D3.js to geoscience data, we found we wanted to simplify basic tasks like making vertical plots, and plotting raster-like data (e.g. seismic) with line plots on top (e.g. horizons). Experience with JavaScript is a must. GitHub repo is here.

The sprint will be at a small joint called MAZ Café Con Leche, located in Santa Ana about 10 km or 15 minutes from the Anaheim Convention Center where the SEG Annual Meeting is happening the following week.

Thank you, as ever, to our fantastic sponsors: Dell EMC and Enthought. These two companies are powered by amazing people doing amazing things. I'm very grateful to them both for being such enthusiastic champions of the change we're working for in our science and our industry. 

If you like the sound of spending the weekend coding, talking geophysics, and enjoying the best coffee in southern California, please join us at the Geophysics Sprint! Register on Eventbrite and we'll see you there.

Get out of the way

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This tweet from the Ecological Society of America conference was interesting:

This kind of thing is not new — many conferences have 'No photos' signs around the posters and the talk sessions. 'No tweeting' seems pretty extreme though. I'm not sure if that's what the ESA was pushing for in this case, but either way the message is: 'No sharing stuff'. They do have a hashtag though, so...

Anyway, I tweeted this in response:

I think this tells you just as much about how broken the conference model is, as about how naïve/afraid our technical societies are.

I think there's a general rule: if you're trying to control the flow of information, you're getting in the way. You're also going to be disappointed because you can't control the flow of information — perhaps because it's not yours to control. I want to say to the organizers: The people you invited into your society are, thankfully, enthusiastic collaborators who can't wait to share the exciting things they heard at your conference. Why on earth would you try to shut that down? Why wouldn't you go out of your way to support them, amplify them, and find more people like them?

But wait, the no-tweeting society asks, what if the author didn't want anyone to share their work? My first question is: why did you give a talk then? My second question is: did the sharer give you proper attribution? If not — you are right to be annoyed and your society should help set this norm in your community. If so — see my first question.

Technical societies need to get over the idea that they own their communities and the knowledge their communities produce. They fret about revenue and membership numbers, but they just need to focus on making their members' technical and professional lives richer and more connected. The rest will take care of itself.

Interested in this topic? Here's a great post about tweeting at conferences, by Jacquelyn Gill. It also links to lots of other opinions, and there are lots of comments.

Image by Rob Salguero-Gómez.

Life lessons from a neural network

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The latest Geophysical Tutorial came out this week in The Leading Edge. It's by my friend Gram Ganssle, and it's about neural networks. Although the example in the article is not, strictly speaking, a deep net (it only has one hidden layer), it concisely illustrates many of the features of deep learning.

Whilst editing the article, it struck me that some of the features of deep learning are really features of life. Maybe humans can learn a few life lessons from neural networks! 

Seek nonlinearity

Activation functions are one of the most important ingredients in a neural network. They are the reason neural nets are able to learn complex, nonlinear relationships without a gigantic number of parameters.

Life lesson: look for nonlinearities in your life. Go to an event aimed at another profession. Take a new route to work. Buy a random volume at your local bookshop. Pick that ice-cream flavour you've never dared try (durian, anyone?).

Iterate

Neural networks learn by repetition. They start with random guesses about what might work, then they process each data point a hundred, maybe 100,000 times, check the answer, adjust weights, and get a little better each time. 

Life lesson: practice makes perfect. You won't get anything right the first time (if you do, celebrate!). The important thing is that you pay attention, figure out what to change, and tweak it. Then try again.

More data

One of the things we know for sure about neural networks is that they work best when they train on a lot of data. They need to see as much of the problem domain as possible, including the edge cases and the worst cases.

Life lesson: seek data. If you're a geologist, get out into the field and see more rocks. Geophysicists: look at more seismic. Whoever you are, read more. Afterwards, share what you find with others, and listen to what they have learned.

Stretch metaphors

Yes, well, I could probably go on. Convolutional networks teach us to create new things by mixing ideas from different parts of our experience. Long training times for neural nets teach us to be patient, and invest in GPUs. Hidden layers with many units teach us to... er, expect a lot of parameters in our lives...?

Anyway, the point is that life is like a neural net. Or maybe, no less interestingly, neural nets are like life. My impression is that most of the innovations in deep learning have come from people looking at their own interpretive and discriminatory powers and asking, "What do I do here? How do I make these decisions?" — and then trying to approximate that heuristic or thought process in code.

What's the lesson here? I have no idea. Enjoy your weekend!

Thumbnail image by Flickr user latteda, licensed CC-BY. The Leading Edge cover is copyright of SEG, fair use terms.