Author Archives: Sean

Unblock IP address from connecting via SSH

I manage a small cluster at work and occasionally students get their IP address banned by entering the wrong password when logging into the cluster. I don’t fix the problem often enough to remember how to do it, so I … Continue reading

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Probability of World Cup Group Draw

The lineup for the 2018 FIFA World Cup is now complete, and the teams have been sorted into pots ahead of the group stage draw on December 1st. All draws are not equally likely, so what teams is your team … Continue reading

Posted in Football, Python | 7 Comments

Correlation of mean transfer spend and UEFA coefficient

How does a countries mean transfer spend relate to its UEFA coefficient?

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Most expensive Premier League football transfer of all time: Rio Ferdinand

No, this post isn’t 15 years late, Rio Ferdinand really did cost “more” than Paul Pogba…

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Passwordless SSH on CentOS

The CentOS wiki page misses out a crucial step in setting up passwordless SSH.

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Complex Reflection Groups

After a spring clean I came across a talk I gave on the classification of complex reflection groups back in March 2011.

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Rescan Wireless Networks on Ubuntu

Sometimes I can’t find wireless networks which I know exist (on Ubuntu 16.04). Forcing the wireless interface to rescan fixes the problem. 

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Distribution of Pancake Day

Today is pancake day and it got me thinking about the fact that I remember the day falling on my birthday (March 7th) just once in my lifetime. How long will I have to wait until it next falls on … Continue reading

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Delete large number of jobs with SGE

Sometimes I accidentally add lots of jobs to our SGE queue and want a quick way to delete them.

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Relationship between Car Insurance Price and Population Density

There was some discussion in my office today about the correlation between car insurance prices and where you live. The idea being that the prices are correlated with population density.

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