I'm Gavin Leech, a data scientist at the giant insurer AXA 4. I write words and code about things - important things or, failing that, interesting things, or, failing that, boring true things. My favourite thing to write about is technical solutions to philosophical problems.

Technically an EA blog, though I don't consider this a blog. (Blogging is more speech than writing.)

You can contact me by email, or anonymously here, or extremely privately (via PGP) here.

Now

* Work: Automating risk pricing models with Spark ML
* Work: Building a summer internship programme
* Writing: how utility theory explains the sometime rationality of insurance
* Learning: constrained nonlinear optimisation, GLMs, Metropolis-Hastings.
* Exercise: Per week - 60mi cycling for commute, 2hrs yoga, 1hr awesome home dumbbells.
* Experimentation: Trying the Flow stack, seeing if there's any effect besides the caffeine.
* People: EA London events.
* Reading: Hirschman, Spiegelhalter, Markham, Soares.
* Watching: 'Mob Psycho 100'. Sheer joy.

Giving

I'm a member of Giving What We Can, people who pledge substantial amounts of their lifetime income to the most effective charitable causes. I'm donating 10% this year, aiming at 50% overall 2. My reasoning on the most important causes, and my present basket of charities is forthcoming.


I am cause-neutral (in the sense that I will support whatever is highest value, to the extent that objective evaluation is possible) and cause-sceptical (in the sense that we don't really know what the best thing to do is).

Psychology

  1. POWER: Social status and prestige, control or dominance over people and resources.
    ACHIEVEMENT: Personal success through demonstrating competence according to social standards.
    HEDONISM: Pleasure or sensuous gratification for oneself.
    STIMULATION: Excitement, novelty, and challenge in life.
    SELF-DIRECTION: Independent thought and action - choosing, creating, exploring.
    UNIVERSALISM: Understanding, appreciation, tolerance, and protection for the welfare of all people and for nature.
    BENEVOLENCE: Preservation and enhancement of the welfare of people with whom one is in frequent personal contact.
    TRADITION: Respect, commitment, and acceptance of the customs and ideas that traditional culture or religion provide.
    CONFORMITY: Restraint of actions, inclinations, and impulses likely to upset or harm others and violate social expectations or norms.
    SECURITY: Safety, harmony, and stability of society, of relationships, and of self.


Misc

Epigram


It is equally fatal to the spirit to have a system and to not have a system.
One will likely have to combine the two. 1
— Friedrich Schlegel


...there is in men and women a motivation stronger even than love or hatred or fear. It is that of being interested — in a body of knowledge, in a problem, in a hobby, in tomorrow’s newspaper.
— George Steiner


Coding

I've been employed to code for 5.2 years 5. Of which, I've been employed in machine learning for 2.6 years.

It is some career. So far I have worked on a precision methadone pump, a website generator for bed & breakfasts, secure off-site credit card storage, procurement streamlining for e.g. 'aerospace' companies, a metre-precise 3D model of Britain's rivers, a performance dashboard for use by secondary school teachers, medical risk scoring models, countermeasures against machine-learning model extraction...

Experience with

Antagonism between language communities is a really clear example of how strong identities cause perversities.

I have written production code in
  • Python (Raw, Pandas, PySpark): 9
  • Spark 10
  • C# 11
  • Typescript 12
  • nodeJS 13
  • Pig Latin 14
  • bash 15
  • Oozie XML 16
  • PHP 17
I also have side projects in
  • Java : All my Master's degree work: Game of Life, Vigenere cipher, .
  • Scala : Just Project Euler so far.
  • Rust : Just Project Euler so far.
  • Powershell: e.g. a web scraper (before Python was provisioned). 5
  • bash : An archiver for hyperlinks.
  • Jekyll : this itself.

Frameworks, tools, stacks, hardware

Stored as JSON here.

Elsewhere

Inspired by

Title

An Iain Banks allusion: his powerful protagonists tease pompous people by taking names with as little gravitas as possible. To take the arg min of something is to find the thing which results in its lowest value.

Endorsements


Utterly charming. In the nature of such lists, one does not expect to agree with every, single one---of course not. But the lists exhibit a lively and critical mind, unwilling to follow the usual party lines.
– Deirdre McCloskey 6


I'm honoured to be on your list [of favourite books].
– Robin Hanson 7


Nice image, young man. You may be a writer.
– Will Self 8



Also, my mum says I'm cool.

Identity

I try not to identify as things. My premises, projects and preferences say overwhelmingly more about me than my social identity does.

Tone

I'm sometimes told I'm too strident. I'll accept this, because constant hedging is unreadable, more annoying than authoritativeness. Also because strong claims galvanise opposition: as long as they're reasonable as well as strong, hopefully this stimulus creates value.

Anyway I'm not as sure as I sound: there's a comment box under every piece, call me out.

Why so many quotations?

Well, they're the densest store of insight. We are not empiricists by nature or by culture, so they are my concession to the apeish narrative side of mind. That quotes page is like a message digest of 10 years of me reading and learning.

I sometimes regret my instinctual distrust of Twitter: a lot of contemporary aphorists must be whiling away the years on there.

Metrics

Here are scales for rating all kinds of things.

Loss function

Above all I hope to beat the trend spotted by Robin Hanson about independent scholars:

over time amateurs blow their lead by focusing less and relying on easier, more direct methods. They rely more on informal conversation as analysis method, they prefer personal connections over open competitions in choosing people, and they rely more on a perceived consensus among a smaller group of fellow enthusiasts. As a result, their contributions just don’t appeal as widely or as long.

Gavins Leeches

Illnesses

I suffer from degenerative telomere erosion, gradually cognivorous amyloid growth, irreversible DNA methylation, imperceptible p16 poisoning, increasingly lazy kinases, and so ultimately oxygen poisoning, like everyone.

What's with all these accordions?

Information hiding is a basic condition of good large software; these accordions are a prose analogue. The hope is that, by tucking away wires, I can write long things without triggering anyone's TL;DR reflex.

It also sort of simulates a dialogue with the reader: I plant a question, and then they prompt for the response.
  1. Es ist gleich tödlich für den Geist, ein System zu haben, und keins zu haben. Es wird sich also wohl entschließen müssen beides zu verbinden.
  2. (or an equivalent value of my labour.)
  3. Opinions expressed are solely my own and do not express the opinions of my employer, etc, etc.
  4. If you count SAS. (If you do, I was employed to code before I learned to Code.)

    Note that just being 'employed to code' says surprisingly little about your ability. And almost nothing about your possession of the spiritual advantages of technical life.
  6. Comment on my "vade mecum" book list including Age of Em.
  7. Here, 21/11/14.
  8. e.g. a computational linguistics wrapper
    e.g. a full notebooked ML pipeline, from sparse raw csvs to GBM to policy implications.
  9. e.g. An ironclad medicine pump controller with WPF.
  10. e.g. A CRUD procurement app with Angular and .NET.
  11. e.g. a secure pharmacy record ("Rx") system.
  12. e.g. Various YARN batch jobs, processing a few TB then emailing out regular tabular summaries.
  13. e.g. Debugging HDFS schema issues with Avrotools.
  14. e.g. chaining Shell and Pig scripts to crunch and mail reports.
  15. e.g. fairly complex websites, Laravel prototyping, a cURL handler for a credit card storage API.