lann

• 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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• Regression with Annoy (cont’d)

  After a year and half, a lot of things changed, and annoy also changed the splitting strategy too. However, I always wanted to do a proper follow up to the original post, where I compared boosting to Annoy. I still remember the reason I started that (flawed) experiment was because I found boosting easy.

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• Quick experiment, boosting vs annoy

  While following through the Statistical Learning course, I came across this part on doing regression with boosting. Then reading through the material, and going through it makes me wonder, the same method may be adapted to Erik Bernhardsson‘s annoy algorithm.

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• Further Hack on the Multi-Dimensional Approximate Neighbour Search

  Traversing a tree structure often involves writing a recursive function. However, Python isn’t the best language for this purpose. Therefore I started flattening the tree into a key-value dictonary structure. Logically it is still a tree, but it is physically stored as a dictionary. Therefore it is now easier to write a simple loop to traverse it.

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Random Posts

• Deploying docker containers with HAProxy on a VPS

  With most of my stuff more or less set, I guess it is time to start documenting the steps before I forget. So I heard a lot of good things about docker for quite some time, but haven’t really have the time to do it due to laziness (plus my relatively n00b-ness in the field of dev-ops). Just a few months ago, I decided to finally migrate away from webfaction (thanks for all the superb support) to a VPS so I can run more things on it.

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• Blending ACL and FSM-based Workflow

  After reading through the documentation, I find that the role based ACL and work flow can be more tightly integrated. Therefore I made all the transaction into many FSMs and my work flow component now consists of one work flow library and one work flow management model. As I am going a more normalized design (I use denormalized design in work as it deals with a lot of documents, however for a small project like mine, a denormalized design should do well).

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• Imperfect Reimplementation of Lists in PHP

  Long long time ago when I was working with Prolog, I was introduced to list. Unlike arrays in most popular programming languages, we weren’t really able to access to a particular member directly. Every list is constructed in a chain-like structure.

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• Statistical Analysis for Social Audit Project

  This is the formal draft of my statistical analysis report for the social audit project previously mentioned here. As the project is public by nature, I am cross-posting here for own reference.

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• Abusing PHP Again: Convert meeTrainer’s CSV to GPX

  The Sports Tracker app for my awesome Nokia N9 is not receiving any updates and doesn’t look like things are going to change any time soon. Recently the development team at Sports Tracker published a status update post and sadly there’s no mention of N9 port at all. It’s really sad considering how incomplete the N9 port is at the moment (horrible GPS positioning, no pedometer to name a few).

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