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

Visualizing neural networks from the nnet package

March 4, 2013
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Visualizing neural networks from the nnet package

Neural networks have received a lot of attention for their abilities to ‘learn’ relationships among variables. They represent an innovative technique for model fitting that doesn’t rely on conventional assumptions necessary for standard models and they can also quite effectively handle multivariate response data. A neural network model is very similar to a non-linear regression

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PCA to PLS modeling analysis strategy for WIDE DATA

March 2, 2013
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PCA to PLS modeling analysis strategy for WIDE DATA

Working with wide data is already hard enough, add to this row outliers and things can get murky fast. Here is an example of an anlysis of a wide data set, 24 rows  x 84 columns. Using imDEV, written in R, to calculate and visualize a principal components analysis (PCA) on this data set. We find that

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Adding Labels to Points in a Scatter Plot in R

Adding Labels to Points in a Scatter Plot in R

What’s the Scatter? A scatter plot displays the values of 2 variables for a set of data, and it is a very useful way to visualize data during exploratory data analysis, especially (though not exclusively) when you are interested in the relationship between a predictor variable and a target variable.  Sometimes, such data come with categorical

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The MaxDiff Killer: Rank-Ordered Logit Models

February 27, 2013
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Compared to MaxDiff (Sawtooth Software), ranked-order logit modeling:simplifies data collection without needing additional software to generate experimental designsreduces respondent burden making the task easier and seemingly ...

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The Paul Tol 21-color salute

February 27, 2013
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The Paul Tol 21-color salute

You may or may not know that PerformanceAnalytics contains a number of specific color schemes designed for charting data in R (they aren’t documented well, but they show up in some of the chart examples). I’ve been collecting color palates for years in search of good combinations of attractiveness, relative weight, and distinctiveness, helped along

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Simplify frequency plots with ggplot in R #rstats

February 25, 2013
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Simplify frequency plots with ggplot in R #rstats

Update March 5th All downloads are now accessible from my script page! Summary This posting shows how to plot frequency plots using the ggplot-package in R. Compared to SPSS standard outputs, you will learn how to create appealing diagrams ready … Weiterlesen →

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Reproducible research with R, Knitr, Pandoc and Word

February 25, 2013
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Add references and a style sheet Below I briefly outline why Pandoc is an essential part of my research workflow, and demonstrate how to seamlessly integrate it with a bibliographic system and code written in R to produce high quality word or pdf documents. I also...

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the BUGS Book [guest post]

February 24, 2013
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the BUGS Book [guest post]

(My colleague Jean-Louis Fouley, now at I3M, Montpellier, kindly agreed to write a review on the BUGS book for CHANCE. Here is the review, en avant-première! Watch out, it is fairly long and exhaustive! References will be available in the published version. The additions of book covers with BUGS in the title and of the corresponding

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Copying Data from Excel to R and Back

February 24, 2013
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Copying Data from Excel to R and Back

A lot of times we are given a data set in Excel format and we want to run a quick analysis using R's functionality to look at advanced statistics or make better visualizations. There are packages for importing/exporting data from/to Excel, but I have f...

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Copying Data from Excel to R and Back

February 23, 2013
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Copying Data from Excel to R and Back

A lot of times we are given a data set in Excel format and we want to run a quick analysis using R's functionality to look at advanced statistics or make better visualizations. There are packages for importing/exporting data from/to Excel, but I have found them to be hard to work with or only work with old versions of...

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