Update on Dissertation & Ubuntu

If you're not aware, I am doing my dissertation on an algorithm called Coupling from The Past algorithm, also known as Propp-Wilson algorithm, an interesting part of Markov chain Monte Carlo. Interested readers can view the links to wikipedia.

Much work has been done on applying this algorithm to Markov chains (random fields) with monotonic structure. I've come up with a way to apply this algorithm to a specific model without a monotonic structure called the Potts model.

Download my "partly done" dissertation here, will be expecting to complete it within the next 2 weeks.

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On a lighter note, I've finally decided to give Ubuntu a try, well at least I'm fairly impressed with the reviews it's getting for Feisty Fawn(7.04).

I've always been an OpenSuSE user since 10.1. If you are a linux person, you would probably notice this website called distrowatch.com. It's a site which "watches" all the linux distros there are out there and rank them in terms of popularity(page hit rank). OpenSuSE has always been in the 2nd spot since the day I found out about it, and Ubuntu has always been the champion of champion there.

Needless to say, there must be reasons why they are the champion to the distro games. From all the reviews I've read about Ubuntu, it's always stated that it is THE EASIEST desktop linux to use ever. If you know how to operate windows, you WILL know how to operate ubuntu, period.

The reason why I chose OpenSuSE over Ubuntu is that I was curious on which windows manager I would prefer, KDE or GNOME. And since OpenSuSE provides the option to install both and use either one for each session, I ended up installing it in my laptop.



Go here if you're interested in giving ubuntu a try. They deliver free(and the CDs are free too) to anywhere in the world, even in Timbuktu. No harm right?


I'm definitely gonna go all out to promote Ubuntu if my leetle project MORSEHack kicks off.

Until next time, folks.

Job Hunt

Updates on my job hunt, to whoever who wants to offer me a job.

Watson Wyatt - Rejected
Towers Perrin - Rejected
PwC - Rejected
Legal & General - Rejected
MercerHR - Phone interview Thursday Done, Waiting results
Groupama - Yet to submit(Pending email reply from HR)

Oh why oh why so hard to get a job 1? Nevermind, try try again.

Anybody got any connections into the actuarial field?

Burning Midnight Oil

It's been my favourite activity for the past few weeks. I can bet none of you work at odd hours like me. My normal working time is between 8.30 at night to 6/7 in the morning. I find it easier to work in a quiet environment when nobody's in the computer centre.

Just a clip of what I'm working on today. Yup, you bet, my dissertation. Now I have to freaking find a way to draw out all the triangles, all these just to make the animation nice to the eyes. And of course allowing one to understand what my function does. Halfway there now, hopefully I can get it done by tonight.


So any helpers? Anybody out there who is fluent in Mathematica? Please...... pretty please......

Job to do:

1. Arrayplot of the Potts model


2. Plot of barycentric coordinates


3. Combine both side-by-side


4. Explain the whole method out(typeset in TeX)
   

Simulating Ising model with CFTP

I should've made this post long time ago.


I have a working code on how to simulate an exact sample of an Ising model using Coupling from the Past method. This is of course going to be the front section of my dissertation on which I'm starting to type out(soon I hope).


Anyway I've written the code on Mathematica and it can be downloaded from


http://www.uploading.com/files/48AGO45J/ising_CFTP_noisy_besag_.nb.html






Just load the file in Mathematica and evaluate notebook.

A description of the diagram above:

• The red sequence starts from the maximum state, i.e. all +1 states.
• The blue sequence starts from the minimum state, i.e. all -1 states.
• We obtain exact sample if at time 0, the final red matches the final blue.
• The yellow/green sequence shows states which are different(yellow) and states which are the same(green) between the red and blue diagrams on each side.

Currently I am(almost successfully) completing a program which samples a 3-state Potts model. However, improvements I would like to make to the above Ising model is a method of testing whether my model is in fact a good sample.

Comments and feedbacks are appreciated. I accept any questions.

Note: A method I use to speed up the model above is the Besag coding trick. You can read more about it from my presentation here.

Presentation

http://www.uploading.com/files/F5BJPCHR/Presentation1.ppt.html

short 5 minute presentation about the subject