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Free eBook: Bayesian Reasoning and Machine Learning

bayesian-learning-ebookWhile studying for the Coursera Machine Learning lecture I attended last year, my learning partner Dimitris L. recommended we should use the Bayesian Reasoning and Machine Learning book by Prof. David Barber as complementary literature. David Barber is currently a professor in Information Processing in the department of Computer Science UCL where he develops novel information processing schemes, mainly based on the application of probabilistic reasoning. As the title of the book suggests, it is all about the concepts and techniques behind Bayesian reasoning and machine learning:


Machine learning methods extract value from vast data sets quickly and with modest resources. They are established tools in a wide range of industrial applications, including search engines, DNA sequencing, stock market analysis, and robot locomotion, and their use is spreading rapidly. Continue reading ‘Free eBook: Bayesian Reasoning and Machine Learning’

What is the Machine Learning class by Prof Ng on Coursera like? My experiences

machine-learning-logoSometime last year in October, I decided to learn more about big data, machine learning and predictive analytics. I gave Coursera a try and enrolled in the 10 weeks  Machine Learning class by Prof Andrew Ng. from Stanford University [1-4]. Prof Ng. is one of the world renowned experts in the field of machine learning, the director of the Stanford AI Lab,  a truly amazing teacher and one of the co-founder of Coursera.

For those who do not know Coursera: Coursera is an educational technology company which is offering free massive open online courses. It has cooperations with universities all around the globe and offers courses in computer science, engineering, physics, humanities, medicine, biology, social sciences, mathematics and business.

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Using OpenRefine to gain insights into, cluster, clean and enrich messy data

OpenRefine logoImagine the following scenario: You get this file (Excel, CSV, Text, XML,…) containing a list with lots of customer, vendor or project data and you want to structure and clean the data before you can use it to do some analytics, reporting, or other processing steps on it . There are a lot of duplicate entries, names are spelled in different ways, everything is a big mess and a manual clean up will cost you a few hours of your precious time…


OpenRefine (formerly Google Refine) is a free and open source application which allows you to explore data (generate insights), clean and transform it using powerful scripting possibilities and to reconcile or match it with data from any kind of webservice or databases like Freebase. The possibilities are endless since it is possible to extend your dataset with all kind of data available through webservices. In addition to the core OpenRefine product, a growing list of extensions and plugins  is available. [2]

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Using SQL WITH clause to create temporary static tables at query time

A few days ago, I came across the following problem: I currently work on a project where I am the responsible of an application which generates entries to a log table every time a job is executed. This table contains a lot of information on statuses of jobs, possible problems, exceptions, duration, aso. I was working on some analytics on this data and needed to enrich the data by the version of the software which generated the log entry (since we were not capturing this in the log table). From our configuration management tool, I was able to extract the dates when which versions of the software was deployed in production


My intention was to create a temporary table to join onto the  logged entries, but I didn´t want to create the tables on the Oracle server (mainly because they would have been just temporary tables and because the schema-user I was using didn´t have the rights to create tables).

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Freiheit im Internet

Nach längerer Zeit gibt es dann auch mal wieder einen neuen Eintrag in meinem Blog ;). Ich war die letzte Zeit viel beschäftigt; unter anderem mit dem Verfassen der Arbeit über die es in diesem Eintrag geht:

Im Sommersemester 2008 habe ich im Rahmen des Seminars Wissenschaftler und Ethik an der TUM eine Arbeit über die Freiheit im Internet geschrieben. Hierbei habe ich besonders die Zensur im Internet untersucht und die aktuellen Zensurmaßnahmen in verschiedenen Ländern und insbesondere China analysiert.


Freiheit im Internet – Ausarbeitung
Freiheit im Internet – Vortrag

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Nokia E51 – VPN Installation Tutorial

Nokia E51 vpn tutorialWie versprochen werde ich auch mal auf Deutsch bloggen, also hier mein erster deutscher Blogeintrag: Diese Woche habe ich mir ein neues Spielzeug gegönnt, das Nokia E51. Ich will an dieser Stelle nicht unbedingt über die Vorzüge des Nokia E51 referieren und das Handy im Detail erklären, vielmehr will ich ein kleines Tutorial bereit stellen, wie man einen VPN Client auf dem Nokia E51 installiert und wie man sich mit einem VPN Netz verbindet. Da ich für die Installation und Konfiguration des VPN-Clients keine ordentliche Beschreibung im Internet gefunden habe und einige Zeit investiert hab, dachte ich mir ich schreib dieses Turorial inkl. Screenshots um Ihnen die Installation zu erleichtern.

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Evaluating the Architectural Coverage of Runtime Traces

  • This post contains a downloadable version of my Bachelor Thesis I wrote to complete my studies in computer science at the Technical University Kaiserslautern. The thesis was conducted externally at the Product-Line Engineering Department of the Fraunhofer Institute for Experimental Software Engineering in Kaiserslautern.

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