Based on the book Compact Stars by N. K. Glendenning a general relativistic treatment of pressure and energy in compact stars is given, followed by simple models of neutron and quark stars. Hypothetical strange quark matter and strange stars are introduced highlighting the importance of sub-millisecond pulsar detections. (Note: this is a student paper I wrote sometime in 2008-2010.)

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I run Monte Carlo simulations of content production over random Watts-Strogatz graphs to show various effects relevant to modeling and understanding Randomized Controlled Trials on social networks: the network effect, spillover effect, experiment dampening effect, intrinsic dampening effect, clustering effect, degree distribution effect and the experiment size effect. I will also define some simple metrics to measure their strength. When running experiments these potentially unexpected effects must be understood and controlled for in some manner, such as modeling the underlying graph structure to establish a baseline.

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Even since I've had a 386 in my room as a teenager, I've taken computers apart and modified and upgraded them. When getting a new workstation computer, I have never bought a pre-assembled one (like a Dell or HP), I always buy the components and build it myself. I've been doing this for 30+ years, so I'm used to it, it's part of my lifecycle. I built my current workstation in 2022, but due to reasons I describe in this post, I've been making a fair amount of modifications to it ever since. Finally, now in 2024 April, I feel that the system has come together and is perfect — I don't want to or plan to make any more changes to it.

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For the past 8 years I've been using Cloud9 for writing code in the cloud, and I can wholeheartedly recommend it: it just works for me. 7 years ago AWS acquired the company, so the project is no longer developed. However, this is not a problem, since it still just works. The only problem I ever had was a minor UI bug, which I fixed in a couple of minutes, as detailed in this post. This was possible because Cloud9 is open-source. I ❤️ open source.

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A compilation of academic-style papers I have written over the years.

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I clean up the code I wrote for earlier posts, and run simple trading experiments.

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I investigate the volatility of aggressive take-profit strategies on tech stocks.

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I investigate the volatility of some securities, and its stability over time.

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It is the beginning of the year — a good time to reflect on the previous year and make plans for the year ahead. I wrote this document for my team members in 2024 January to kick off the year. This is an abridged version with sensitive content removed.

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I wrote this document for my team members — Data Scientists and Data Engineers — to help them do a better on their annual performance reviews.

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In this follow-up to the previous article about writing a C++ version of the Unix command-line utility wc, I make some modifications to beat my system wc in performance tests.

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In this follow-up to the previous article about writing a C++ version of the Unix command-line utility wc, I make the class structure more complicated to keep separate concerns and functionality in different C++ classes. The result ends up being significantly more complex than the original, but does not make the overall program easier to understand or modify.

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After reading the excellent book Beautiful C++ about the language's latest features, I implement the Unix command-line tool wc in modern C++.

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A review of the Donald MacKenzie's book Trading at the Speed of Light, which gives an excellent history and inside-peek of the world of High Frequency Trading, or HFT.

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I describe the concept of Marketing Mix Modeling using Google's LightweightMMM library.

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The Hero's Journey, or Monomyth, is a narrative pattern identified by scholar Joseph Campbell that appears across a wide range of cultures and eras, and is also a useful mental model in Leadership.

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I discuss five lessons from large-scale experiments conducted by Google, Bing, Netflix and Alibaba: Kohavi's 1 out of 3 rule, Google's 41 shades of blue, Bing's unexpected big win, Alibaba's personalization experiment and Netflix' movie image personalization.

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I give examples of "unintuitive" conditional probabilities and discuss Simpson's paradox.

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I run experiments to determine whether, or to what degree, GPT-4 has developed an comprehension of spatial relationships. I find that it it significantly better than GPT-3.

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In this post, I describe the Pareto Principle, the Peter Principle, the Rumsfeld Matrix, Servant Leadership and Pygmalion Effect, and finally Goleman's Emotional Intelligence Model.

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