957 search results for "how to import image file to r"

Looking to boxplots (Shootout 2012)

January 20, 2013
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Looking to boxplots (Shootout 2012)

Boxplots are a nice way to compare the three sample sets of the Shoot-out 2012 data files.There is a category variable (Set) in the data frame with the labels (Cal = Training Set, Test = Test Set and Val = Validation Set). # IMPORTING THE SAMPLE SETS #...

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texreg: A package for beautiful and easily customizable LaTeX regression tables from R

January 20, 2013
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texreg: A package for beautiful and easily customizable LaTeX regression tables from R

There was a very informative post last week showing how the R package stargazer is used to generate nice LaTeX tables from a number of R objects. This package looks very useful. However, I would like to extol the virtues of another R package that converts model objects in R into LaTeX code: texreg. For

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A slightly different introduction to R, part I

January 19, 2013
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A slightly different introduction to R, part I

Note in Swedish: Jag hoppas läsaren ursäktar att jag skriver på engelska då och då. This will be a brief introduction to using the statistics software R for biologists who want to do some of their data analysis in R. There are plenty of introductions to R (see here and here, for example; these are

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How much can we learn from an empirical result? A Bayesian approach to power analysis and the implications for pre-registration.

January 18, 2013
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How much can we learn from an empirical result? A Bayesian approach to power analysis and the implications for pre-registration.

Just like a lot of political science departments, here at Rice a group of faculty and students meet each week to discuss new research in political methodology. This week, we read a new symposium in Political Analysis about the pre-registration of studies in political science. To briefly summarize, several researchers argued that political scientists should

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How much can we learn from an empirical result? A Bayesian approach to power analysis and the implications for pre-registration.

January 18, 2013
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How much can we learn from an empirical result? A Bayesian approach to power analysis and the implications for pre-registration.

Just like a lot of political science departments, here at Rice a group of faculty and students meet each week to discuss new research in political methodology. This week, we read a new symposium in Political Analysis about the pre-registration of studies in political science. To briefly summarize, several researchers argued that political scientists should

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Visually Comparing Return Distributions

January 18, 2013
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Visually Comparing Return Distributions

Here is a spot of code to create a series of small multiples for comparing return distributions. You may have spotted this in a presentation I posted about earlier, but I’ve been using it here and there and am finally satisfied that it is a generally useful view, so I functionalized it. When visually comparing

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Power Calculations – relationship between test power, effect size and sample size

January 17, 2013
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Power Calculations – relationship between test power, effect size and sample size

I was interested in modeling the relationship between the power and sample size, while holding the significance level constant (p = 0.05) , for the common two-sample t-Test. Luckily R has great support for power analysis and I found the function I was looking for in the package pwr. To calculate the power for the two-sample T-test

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If SPSS can factor analyze MaxDiff scores, why can’t R?

January 17, 2013
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If SPSS can factor analyze MaxDiff scores, why can’t R?

Answer:  The variance-covariance matrix containing all the MaxDiff scores is not invertible.  R tells you that, either with an error message or a warning.  SPSS, at least earlier versions still in use, runs the factor analysis witho...

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Creating a random calendar with R

January 14, 2013
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Creating a random calendar with R

Sometimes this is my life. But it’s so satisfying when you write a program that saves you time! Here is an example. The Problem:  For several years at Hopkins I have been involved in teaching a large (500+ person) introductory Biostatistics class. This … Continue reading →

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Using TeXmacs as an interface for R

January 14, 2013
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Using TeXmacs as an interface for R

Using TeXmacs as an interface for R (part 1)(This post was copied from my post at wordpress. Because I didn't manage to switch r-bloggers.com to use that blog, I'm reposting it here....) A nice, but not very well known, interface to R isTeXmacs. (I...

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