770 search results for "how to import image file to R"

Benchmarking time series models

December 29, 2011
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Benchmarking time series models

This is a quick post on the importance of benchmarking time-series forecasts.  First we need to reload the functions from my last few posts on times-series cross-validation.  (I copied the relevant code at the bottom of this post so you don't...

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Portfolio Optimization in R, Part 4

December 23, 2011
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Portfolio Optimization in R, Part 4

This post will conclude the portfolio optimization series.  In this post, we will construct a trading strategy based on portfolio optimization and test the results against the CAPM market portfolio as well as another strategy.It is worth reiterati...

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data.frame objects in R (via “R in Action”)

December 18, 2011
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data.frame objects in R (via “R in Action”)

The followings introductory post is intended for new users of R.  It deals with R data frames: what they are, and how to create, view, and update them. This is a guest article by Dr. Robert I. Kabacoff, the founder of (one of) the first online R tutorials websites: Quick-R.  Kabacoff has recently published the book ”R Read more...

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Portfolio Optimization in R, Part 1

December 17, 2011
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Portfolio Optimization in R, Part 1

I briefly mentioned in my last post; that I was fooling around with portfolio optimization in R.  This post will the first in a series on the topic of portfolio optimization. Please note, nothing I am about to say should be taken as advice for investing.  These results are based on prior observed returns and the future...

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IRIS Flower Data Set (R-001)

December 17, 2011
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IRIS Flower Data Set (R-001)

IRIS Flower Data SetEste es el Link a Wikipedia donde podéis encontrar los datos que utilizó Fisher en su trabajo de 1936. Ya hemos trabajado con estos datos en Excel y los continuaremos usando en nuevas entradas.En este link, podemos ver las fotos de las flores (IRIS en castellano son lírios).Represento como LS (longitud del sépalo), AS...

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Bayesian inference and the parametric bootstrap

December 15, 2011
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Bayesian inference and the parametric bootstrap

This paper by Brad Efron came to my knowledge when I was looking for references on Bayesian bootstrap to answer a Cross Validated question. After reading it more thoroughly, “Bayesian inference and the parametric bootstrap” puzzles me, which most certainly means I have missed the main point. Indeed, the paper relies on parametric bootstrap—a frequentist

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Running your R and LaTeX Infrastructure from a portable USB Drive

December 9, 2011
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Running your R and LaTeX Infrastructure from a portable USB Drive

On my road to eventually running all of my programs off an USB device I’ve gotten a little bit closer yesterday thanks to input from Duncan Murdoch and Yihui Xie. Eventually running the entire Windows OS off a USB drive would be nice (not talking about running it as a Virtual Machine, but to have … Continue reading...

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MCMC chain analysis and convergence diagnostics with coda in R

December 9, 2011
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MCMC chain analysis and convergence diagnostics with coda in R

Last week, I gave a seminar about MCMC chain analysis and convergence diagnostics with coda in R, and I thought a summary would make a nice post. As a prerequisite, we will use a few lines of code, very similar to a previous post on MCMC sampling. In the code, we create some test data…

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Example 9.16: Small multiples

November 29, 2011
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Example 9.16: Small multiples

Small multiples are one of the great ideas of graphics visionary Edward Tufte (e.g., in Envisioning Information). Briefly, the idea is that if many variations on a theme are presented, differences quickly become apparent. Today we offer general guida...

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Dealing with R and HANA

November 28, 2011
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Dealing with R and HANA

First things first...what's "R"? Simply put...is a programming language and software environment for statistical computing and graphics. More infomation can be found here R on WikipediaI have code in many programming languages, some of them very commer...

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