If you dabble in reflection seismic analysis, you probably know the Ricker wavelet. We’ve visited it a few times on this blog — Evan once showed how to make and plot one, I looked at some analytic properties of it, and we even played golf with it.The Ricker is everywhere, but it has an important limitation — bandwidth. Its shape in the frequency domain is roughly Gaussian (below, left), which is the reason it only really has…

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Last week I wrote about the turmoil many subsurface professionals are experiencing today. There’s no advice that will work for everyone, but one thing that changed my life (ok, my career at least) was learning a programming language. Not only because programming computers is useful and fun, but also because of the technology insights it brings. Whether you’re into data management or machine learning, workflow automation or just being a more rounded professional, there really…

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At last, 2021 is fully underway. There’s a Covid vaccine. The president of the US is not deranged. Brexit is essentially over. We can go back to normal now, right? Soon anyway… after the summer… right?No.There is no ‘back’ on this thing, only forward. Even if there was a back, there is no ‘normal’. So, as comforting as they are, I try to avoid ideas like ‘recovery’, or ‘getting back to normal’. Instead, I look…

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I recently finished a Udemy machine learning course, and wrote on LinkedIn afterwards: “While I am no [machine learning] expert, this is one step on the way to better skills with [Python]”. So which other steps have I taken along that route to learn more about machine learning?Here I share my thoughts on three books; two of which I have read cover to cover, and the third which I can hardly put down! When students…

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Last week the Data Analysis Study Group of the SPE Gulf Coast Section announced a new machine learning contest (I’m afraid registration is now closed, even though the contest has not started yet). The task is to predict shear-wave sonic from other logs, similar to the SPWLA PDDA contest last year. This is a valuable problem in the subsurface, because shear sonic log is essential for computing elastic properties of rocks and therefore in predicting…

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Last year I wrote a post about annotated equations, and why they are useful teaching tools. But I never shared all the cool examples people tweeted back, and some of them are too good not to share.Let’s start with this one from Andrew Alexander that he uses to explain complex number notation: Paige Bailey tweeted some examples of annotated equations and code from the reinforcement learning tutorial, Building a Powerful DQN in TensorFlow by Sebastian…

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Difficulty rating: Intermediate A few years back I needed to plot some fracture data without specialist software, so I created an Excel spreadsheet with a polar plot and interactive widgets. But thanks to Joe Kington and his awesome mplstereonet library those days are over. Today I want to share with you how to plot two fracture sets on an equal area Schmidt plot with mplstereonet. Here's what we're going to do — and in only…

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Yesterday in Functional but unsafe machine learning I wrote about how easy it is to build machine learning pipelines that yield bad predictions — a clear business risk. Today I want to look at some ways we might reduce this risk.The diagram I shared yesterday tries to illustrate the idea that it’s easy to find a functional solution in machine learning, but only a few of those solutions are safe or fit for purpose. The…

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There are always more ways to mess something up than to get it right. That’s just statistics, specifically entropy: building things is a fight against the second law of thermodynamics. And while messing up a machine learning model might sound abstract, it could result in poor decisions, leading to wasted resources, environmental risk, or unsafe conditions.Okay then, bad solutions outnumber good solutions. No problem: we are professionals, we can tell the difference between good ones…

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I usually write a ‘lookback’ at this time of year, but who wants to look back on 2#*0? Instead, let’s look forward to 2021 and speculate wildly about it!More ways to helpAgile has always been small and nimble, but the price we pay is bandwidth: it’s hard to help all the people we want to help. But we’ve taught more than 1250 people Python and machine learning since 2018, and supporting this new community of…

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