Matthew Walker

Particle Physicist. Data Modeler.

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Why We Built The Best Particle Physics Analysis Framework

There are three major timescales to consider when you’re trying to carry out a particle physics analysis:

  1. How long it takes to figure out what you want to measure or search for and how to do it.
  2. How long it takes you code up the analysis.
  3. How long it takes you to run your code over your data.

There’s a multiplier on 2 and 3 based on how many mistakes you make. If you make a lot of mistakes, you have to spend a long time figuring out what they are and rerunning your analysis on the data. How often you make mistakes is related to how good of a coder you are, but also how good your framework is.

Most particle physics analyses follow a fairly similar workflow. These days, reconstruction of candidate particles (of things like electrons, muons, photons, jets, and others) are produced centrally by the experiment. Then, individual analyses apply their own selection criteria to the different...

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Statistics on HN usage

A few months ago, I created some figures for some various statistics about HN usage. By themselves, I didn’t think they were very interesting, and I’m running some more sophisticated analysis of comments at the moment that was going to accompany them. However, in light of the recent announcement that there will soon be pending comments on HN, I thought there might be some interest in seeing them.

The data for these figures was taken from (now-defunct) HNSearch in mid October 2013, so I only included analysis up to September 30, 2013. I should note that I started the graphs in early 2007 because, though HN dates back to late 2006, there was a fairly long dry spell without any activity.

“Basic” Variables

The first figure is submissions per day. I separated between weekdays and weekends and added a 7-day average curve:

submissionsPerDay.png

The next figure is total (registered) users. I’m not sure how...

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