Blog Archives

Maize trade Part II: Comparison and analysis

February 3, 2013
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Maize trade Part II: Comparison and analysis

Following my last post about the maize network, although interesting but is not very informative. What we are going to do today is to contrast the maize network with the wine trade network.The choice why we have chose wine will become clear after the...

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Maize trade Part I: Generate the network diagram

January 17, 2013
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Maize trade Part I: Generate the network diagram

It has been several month since my last post, partially due to the fact that my laptop was lost and several deadlines was approaching. Fortunately I will be returning to Taiwan and get a new laptop within a week, and will be updating regularly...

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Perculiar behaviour of the sum function

October 3, 2012
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The sum function in R is a special one in contrast to other summary statistics functions such as mean and median. The first distinguish is that it is a Primitive function where the others are not (Although you can call mean using .Internal). This ...

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my Facebook social network

September 29, 2012
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my Facebook social network

I got very excited on making a network diagram of my Facebook network using Ghefi (https://gephi.org/) and submitted my first assignment for the Social Network Analysis course on https://www.coursera.org/. It's middle of the night, so I will ...

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Network of trade

September 22, 2012
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Network of trade

This week,  I got my hands on some agricultural trade data. Trade data are typically extremely dirty so treat with care when you get your hands on them. Lab standard equipments are required.So I decided to look how countries trade by plotting the ...

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Preferential attachment for network

September 15, 2012
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I am currently taking the networked life course on Coursera.org offered by Professor Michael Kearns from the University of Pennsylvania.  I have been took several courses including machine learning, natural language processing since the platf...

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Imputation by mean?

September 13, 2012
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Today, I was briefed that when computing the regional aggregates such as those defined by the M49 country standard of the United Nation (http://unstats.un.org/unsd/methods/m49/m49regin.htm) I should use the regional mean to replace missing values....

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Units and metadata

August 2, 2012
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Handling meta-data is not natural in R, or any traditional rectangular shaped type data storage system.There are several tricks and packages which attempt to solve this problem, with Hmisc using the atrribute feature and the IRange package having its o...

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