Fabian Kostadinov

My Reoccurring Dream of Stealing Away From Military

I had the same dream for years. Once maybe every few months. In it I was in the military. However, actually, I did not really belong there. Not that I really was a soldier or that I had intentionally joined the forces, but me being there was in fact based on a mistake. Yet, I was not able to articulate myself. So the only option left to me in the dream was to steal away in secrecy.

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Four Questions To Ask During A Job Interview

During the last few months, I had several job interviews with different prospective employers. A few weeks ago a working colleague pointed me to four questions that I could ask my prospective employer that would tell me a lot about the working culture I'd join. As my experience with asking these questions was very positive, I thought I publish them here in my blog. To the best of my knowledge, the original (German) version comes from a guy called Lars Vollmer. What follows is nothing but a translation from German to English.

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How I Created a Simple DBMS using GitHub, Jekyll, Prose and Heroku

Recently, I created a simple database management system including user rights management relying on GitHub, Jekyll, Prose, Heroku and a few other open source products. The basic idea is to store all data inside a _data directory in a GitHub repository. A user can access this data through a website (Prose) and manipulate it through a HTML form (JSONForm), but she needs to be authorized to do so (Jekyll-Auth). The solution also offers a simple, yet functional search functionality. Here is a list of products I relied upon:

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Comparing ADF Test Functions in R

In one of my last posts I was not sure how R's different ADF test functions worked in detail. So, based on this discussion thread I set up a simple test. I created four time series:

  1. flat0: stationary with mean 0,
  2. flat20: stationary with mean 20,
  3. trend0: trend stationary with "trend mean" crossing through (0, 0) - i.e. without intercept,
  4. trend20: trend stationary with "trend mean" crossing through (0, 20) - i.e. with intercept 20.
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Cointegration and Total-Least-Squares Regression

I just stumbled over a very nice article authored by Paul Teetor on the use of total least-squares-regression in contrast to ordinary-least-squares regression for cointegration tests. This blog post also explains the same topic.

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