2014 April 19

• Some status updates

  There are a lot of things I want to post to both here and my personal blogs. However I was sucked into sanctuary for the most of last month. I guess after a month of playing, it is probably time to slowly resume my personal projects.

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Random Posts

• Random notes on Pandas and Scikit-learn

  So I first heard about Panda probably a year ago when I was in my previous job. It looked nice, but I didn’t really get the chance to use it. So practically it is a library that makes data looks like a mix of relational database table and excel sheet. It is easy to do query with it, and provides a way to process it fast if you know how to do it properly (no, I don’t, so I cheated).

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• Development virtual machines on OS X using VirtualBox and Ubuntu

  I have been following this excellent guide written by Benjamin Thomas to set up my virtual machine for development purpose. However, when I am starting to configure a Ubuntu Quantal alpha machine, parts of the guide became inapplicable. Hence, this post is written as a small revision to the previously mentioned guide.

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• Understanding potree hierarchy file

  One of my recent tasks involving crawling a lot of geo-tagged data from a given service. The most recent one is crawling files containing a point cloud for a given location. So I began by observing the behavior in the browser. After exporting the list of HTTP requests involved in loading the application, I noticed there are a lot of requests fetching resources with a common rXXX pattern.

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• Regression with 2-means clustering Annoy (non-scientific)

  So apparently Annoy is now splitting points by using the centroids of 2 means clustering. It is claimed that it provides better results for ANN search, however, how does this impact regression? Purely out of curiosity, I plugged a new point splitting function and generated a new set of points.

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• Collaborative Tagging & Folksonomy

  Folksonomy is a neologism of two words, ’folk’ and ’taxonomy’ which describes conceptual structures created by users ^{[4, 5]}. A folksonomy is a set of unstructured collaborative usage of tags for content classification and knowledge representation that is popularized by Web 2.0 and social applications ^{[1, 5]}. Unlike taxonomy that is commonly used to organize resources to form a category hierarchy, folksonomy is non-hierarchical and non-exclusive ^[3]. Both content hierarchy and folksonomy can be used together to better content classification.

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