CO2 Emission Trends

August 23, 2009
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CO2 Emission Trends

“Since 1751 approximately 329 billion tons of carbon have been released to the atmosphere from the consumption of fossil fuels and cement production. Half of these emissions have occurred since the mid 1970s. The 2006 global fossil-fuel carbon emission estimate, 8230 million metric tons of carbon, represents an all-time high and a 3.2% increase

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R help on StackOverflow

August 23, 2009
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R help on StackOverflow

Ever since I began using R about ten years ago, the best place to find R help was on the R-help mailing list. But it is time-consuming searching through the archives trying to find something from a long time ago, and there is no way to sort out the good advice from the bad advice.

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R help on StackOverflow

August 23, 2009
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Ever since I began using R about ten years ago, the best place to find R help was on the R-help mailing list. But it is time-consuming searching through the archives trying to find something from a long time ago, and there is no way to sort out the goo...

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R handy for crunching data

August 23, 2009
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R handy for crunching data

http://www.ibm.com/developerworks/library/l-sc16.html?S_TACT=105AGX52&S_CMP=cn-a-l

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NpptoR: R in Notepad++

August 22, 2009
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NpptoR: R in Notepad++

For those who are scared of Emacs: http://sourceforge.net/projects/npptor/

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Test cointegration with R

Cointegrated pairs of securities are crucial for mean reversion trading portfolio construction, Play with cointegration has several good papers to start with. Should you want to test pairs of securities for cointegration using R, here is an excellent ...

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No success yet, then more animations…

August 20, 2009
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No success yet, then more animations…

So I've been here dealing with the installation of a software that Yihui Xie suggested me to change the format of the animations displayed in R, she told me that all I needed to do was to go to http://imagemagick.org to download ImageMagick for my ope...

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No success yet, then more animations…

August 20, 2009
By
No success yet, then more animations…

So I've been here dealing with the installation of a software that Yihui Xie suggested me to change the format of the animations displayed in R, she told me that all I needed to do was to go to http://imagemagick.org to download ImageMagick for my ope...

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Simple logistic regression on qualitative dichotomic variables

August 20, 2009
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Simple logistic regression on qualitative dichotomic variables

In this post we will see briefly how to implement a logistic regression model if you have categorical variables, or qualitative, organized in double entry contingency tables. In this model the dependent variable (Y) and independent variable (X) are both dichotomies (or Bernoullian).In general, the probability that Y = 1 as a function of predictors is:$$P(Y=1|X=x)=\pi(x)=\frac{exp(\beta_0+\beta_1x_1+\cdots +\beta_kx_k)}{1+exp(\beta_0+\beta_1x_1+\cdots +\beta_kx_k)}$$Our goal...

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Simple logistic regression on qualitative dichotomic variables

August 20, 2009
By
Simple logistic regression on qualitative dichotomic variables

In this post we will see briefly how to implement a logistic regression model if you have categorical variables, or qualitative, organized in double entry contingency tables. In this model the dependent variable (Y) and independent variable (X) are both dichotomies (or Bernoullian).In general, the probability that Y = 1 as a function of predictors is:$$P(Y=1|X=x)=\pi(x)=\frac{exp(\beta_0+\beta_1x_1+\cdots +\beta_kx_k)}{1+exp(\beta_0+\beta_1x_1+\cdots +\beta_kx_k)}$$Our goal...

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ggplot2 Version of Figures in “Lattice: Multivariate Data Visualization with R” (Part 13)

August 20, 2009
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ggplot2 Version of Figures in “Lattice: Multivariate Data Visualization with R” (Part 13)

This is the 13th post in a series attempting to recreate the figures in Lattice: Multivariate Data Visualization with R (R code available here) with ggplot2. Previous parts in this series: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9, Part 10, Part 11, Part 12. Chapter 14

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2 Interesting animations…

August 19, 2009
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2 Interesting animations…

So I haven't had success YET in finding a way to post here the animations, but I thought it would be interesting to show you at least a couple of examples using this software, and I chose 2 pretty interesting ones by Yihui Xie and Xiaoyue Cheng.The fir...

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2 Interesting animations…

August 19, 2009
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2 Interesting animations…

So I haven't had success YET in finding a way to post here the animations, but I thought it would be interesting to show you at least a couple of examples using this software, and I chose 2 pretty interesting ones by Yihui Xie and Xiaoyue Cheng.The fir...

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Have you ever heard about the ‘animation package’?

August 18, 2009
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Well, I had never heard about it, but this morning I was looking for some information about another package and I found and article about this interesting package at 'The R-Journal' (http://journal.r-project.org/), it was on the Vol. 8/2, October 2008, by Yihui Xie and Xiaoyue Cheng, and it says something like..."The animation package (Xie, 2008) uses graphical andother...

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Have you ever heard about the ‘animation package’?

August 18, 2009
By

Well, I had never heard about it, but this morning I was looking for some information about another package and I found and article about this interesting package at 'The R-Journal' (http://journal.r-project.org/), it was on the Vol. 8/2, October 2008, by Yihui Xie and Xiaoyue Cheng, and it says something like... "The animation package (Xie, 2008) uses graphical and other...

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ggplot2 Version of Figures in “Lattice: Multivariate Data Visualization with R” (Part 12)

August 18, 2009
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ggplot2 Version of Figures in “Lattice: Multivariate Data Visualization with R” (Part 12)

This is the 12th post in a series attempting to recreate the figures in Lattice: Multivariate Data Visualization with R (R code available here) with ggplot2. Previous parts in this series: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9, Part 10, Part 11. Chapter 13 – Advanced

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R Coding Style Guide

August 18, 2009
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I was sent this R style guide, and think it looks like it might be a good idea. R can be pretty difficult to read, especially someone else's.

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R Coding Style Guide

August 18, 2009
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I was sent this R style guide, and think it looks like it might be a good idea. R can be pretty difficult to read, especially someone else's.

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The density function

August 18, 2009
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The density function

Today I found such an interesting function called "density", this function computes kernel density estimates, that's why I found it pretty interesting, all you need is:the the data from which the estimate is to be computed the smoothing kernel to be us...

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The density function

August 18, 2009
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The density function

Today I found such an interesting function called "density", this function computes kernel density estimates, that's why I found it pretty interesting, all you need is:the the data from which the estimate is to be computed the smoothing kernel to be us...

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Social Network Analysis Resources for R

August 17, 2009
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Social Network Analysis Resources for R

Social Network Analysis is an increasingly popular tool for modelling dependence structures between social actors. In my department researchers are developing new models for representing such dependence structures (MELNET). In 2007 I gave a talk on my ...

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Headless R / X11 and Cygwin/X

August 17, 2009
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Running R on a Linux server in headless mode (i.e. producing graphics without XWindows running) can be tricky. Some people recommend using a virtual X framebuffer. However, I’ve found that the best approach (at least im my opinion) is to use the ...

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Potential Loss of Arable Land in the Central San Joaquin Valley, CA

August 17, 2009
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Potential Loss of Arable Land in the Central San Joaquin Valley, CA

Rapid urban and sub-urban expansion in the San Joaquin Valley have resulted in the loss of millions of acres of prime farmland in the last 100 years. Approximately 11% of class 1 (irrigated) land and 7% of class 2 land have already been paved over in the Fresno-Madera region (first image below). Recent projections in the expansion of urban...

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High tech, low tech?

August 15, 2009
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High tech, low tech?

Interesting article: http://www.iq.harvard.edu/blog/sss/archives/2006/01/tools_for_resea.shtml

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Cool articles in the New York Time’s: Statistics + R

August 14, 2009
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so these articles are ‘old news,’ but here i am to blog it down before i forget. First article is entitled “For Today’s Graduate, Just One Word – Statistics,” and the second article is entitled “Data Analysts Captivated by R’s Power.” It really does feel re-enforcing and motivating when the NY Times write about your

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Everybody loves R

August 14, 2009
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I found this articles in The New York Times" and I thought it would be nice to share them, By ASHLEE VANCE published on January 6, 2009, check them out, both are pretty interesting:http://www.nytimes.com/2009/01/07/technology/business-computing/07progr...

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Everybody loves R

August 14, 2009
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I found this articles in The New York Times" and I thought it would be nice to share them, By ASHLEE VANCE published on January 6, 2009, check them out, both are pretty interesting:http://www.nytimes.com/2009/01/07/technology/business-computing/07progr...

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First 15 min. volatility impact on the day’s volatility

August 14, 2009
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First 15 min. volatility impact on the day’s volatility

One night I was hooked on this post at elitetrader. I spent couple of hours to find, that a guy is cheating a bit and he didn’t reveal his strategy. Not big deal – free lunch is rear. So, I googled about that guy and one thing catch my attention. In one of his post

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Example 7.10: Get data from R into SAS

August 13, 2009
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Example 7.10: Get data from R into SAS

In our previous entry, we described how to generate a dataset from SAS that could be used for analyses in R. Alternatively, someone primarily using R might want to test the new ”statistical graphics” procedures available starting with SAS 9.2. Her...

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