# 1291 search results for "Latex"

## Animations Understood

May 11, 2013
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When I first saw a graphic made from Yihui’s animation package (Xie, 2013) I was amazed at the magic and thought “I could never do that”. Passage of time… One night I found myself bored and as usual avoiding work. … Continue reading →

## Veterinary Epidemiologic Research: Count and Rate Data – Zero Counts

May 6, 2013
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$Veterinary Epidemiologic Research: Count and Rate Data – Zero Counts$

Continuing on the examples from the book Veterinary Epidemiologic Research, we look today at modelling count when the count of zeros may be higher or lower than expected from a Poisson or negative binomial distribution. When there’s an excess of zero counts, you can fit either a zero-inflated model or a hurdle model. If zero

## How to Calculate a Partial Correlation Coefficient in R: An Example with Oxidizing Ammonia to Make Nitric Acid

Introduction Today, I will talk about the math behind calculating partial correlation and illustrate the computation in R with an example involving the oxidation of ammonia to make nitric acid using a built-in data set in R called stackloss.  In a separate post, I will also share an R function that I wrote to estimate partial correlation.

## AIC & BIC vs. Crossvalidation

May 4, 2013
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Model selection is a process of seeking the model in a set of candidate models that gives the best balance between model fit and complexity (Burnham & Anderson 2002). I have always used AIC for that. But you can also…Read more →

## …start using Sweave, from scratch!

May 1, 2013
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INTRODUCTION Sweave is nothing more, nothing less than the best way R can connect with a text editor, in this case LaTeX. So you don’t know anyting about LaTeX? neither did I 8 months ago… The hyperlinks in this post … Sigue leyendo →

## All you need is text – Markdown (via pandoc) for academia

May 1, 2013
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Many students struggle to find an adequte format for their thesis. Ironically the advent of “modern” WYSIWYG programms seems to make it harder to consistently format a text. While learning LaTeX may be a bit too much to ask for, markdown is a very minimal language that together with pandoc affords all typesetting needs for

## Missing tikzDevice

April 30, 2013
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I love using tikzDevice. When preparing LaTeX documents I switched to prepare all graphs in GNU R and then port them to TeX using tikzDevice. Recently I have moved to GNU R 3.0.0 and was shocked to find that this package is no longer available on CRAN....

## Integrating Documentation and Calculation

April 30, 2013
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Integrating Documentation and Calculation Integrating Documentation and Calculation This post is a first in that I've authored it using RStudio. I would guess most people who work in computational finance or quantitative risk are at least familiar with R. Unfortunately R as...

## Poor man’s integration – a simulated visualization approach

April 29, 2013
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$Poor man’s integration – a simulated visualization approach$

Every once in a while I encounter a problem that requires the use of calculus. This can be quite bothersome since my brain has refused over the years to retain any useful information related to calculus. Most of my formal training in the dark arts was completed in high school and has not been covered

## Using the Golden Section Search Method to Minimize the Sum of Absolute Deviations

$Using the Golden Section Search Method to Minimize the Sum of Absolute Deviations$

Introduction Recently, I introduced the golden search method – a special way to save computation time by modifying the bisection method with the golden ratio, and I illustrated how to minimize a cusped function with this script.  I also wrote an R function to implement this method and an R script on how to apply this