2680 search results for "GIS"

sab-R-metrics: Multiple Regression and Interactions

March 12, 2011
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Last time, I covered ordinary least squares with a single variable. This time, I'll extend this to using multiple predictor variables in a regression, interacting terms in R, and start thinking about using polynomials of certain terms in the regression (like Age and Age Squared). This should be a pretty straight forward tutorial, especially if you've got...

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sab-R-metrics: Multiple Regression and Interactions

March 12, 2011
By

Last time, I covered ordinary least squares with a single variable. This time, I'll extend this to using multiple predictor variables in a regression, interacting terms in R, and start thinking about using polynomials of certain terms in the regression (like Age and Age Squared). This should be a pretty straight forward tutorial, especially if you've got...

Read more »

Analyzing big data with Revolution R Enterprise

March 10, 2011
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This post from Sherry LaMonica is the first in a series from members of the Revolution Analytics Engineering team — ed. Do you know about the big data capabilities in the RevoScaleR package, included with every Revolution R Enterprise installation? RevoScaleR provides a framework for fast and efficient multi-core processing of large data sets. You can visualize and model...

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Comparing two-dimensional data sets in R; take II

March 10, 2011
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Comparing two-dimensional data sets in R; take II

David commented on yesterday's post and suggested to put the continuous fitted distribution in the background and the discrete, empirical distribution in the foreground. This looks quite nice, although there's a slight optical illusion that makes the c...

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Comparing two-dimensional data sets in R; take II

March 10, 2011
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Comparing two-dimensional data sets in R; take II

David commented on yesterday's post and suggested to put the continuous fitted distribution in the background and the discrete, empirical distribution in the foreground. This looks quite nice, although there's a slight optical illusion that makes the c...

Read more »

In case you missed it: February Roundup

March 9, 2011
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In case you missed them, here are some articles from February of particular interest to R users. Revolution R Enterprise 4.2 is now available to subscribers, and for free download to academics. A brief report from the Strata: Working with Data conference, and a comprehensive review from Ted Leung. A profile of prolific R contributor, Dirk Eddelbuettel. A list...

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Comparing two-dimensional data sets in R

March 9, 2011
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Comparing two-dimensional data sets in R

I wanted to fit a continuous function to a discrete 2D distribution in R. I managed to do this by using nls, and wanted to display the data. I discovered a nice way to compare the actual data and the fit using ggplot2, where the background is the real ...

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Comparing two-dimensional data sets in R

March 9, 2011
By
Comparing two-dimensional data sets in R

I wanted to fit a continuous function to a discrete 2D distribution in R. I managed to do this by using nls, and wanted to display the data. I discovered a nice way to compare the actual data and the fit using ggplot2, where the background is the real ...

Read more »

Forest plots using R and ggplot2

March 9, 2011
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Forest plots using R and ggplot2

Abhijit over at Stat Bandit posted some nice code for making forest plots using ggplot2 in R. You see these lots of times in meta-analyses, or as seen in the BioVU demonstration paper. The idea is simple - on the x-axis you have the odds ratio (or what...

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Splitting a Dataset Revisited: Keeping Covariates Balanced Between Splits

March 8, 2011
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Splitting a Dataset Revisited: Keeping Covariates Balanced Between Splits

In my previous post I showed you how to randomly split up a dataset into training and testing datasets. (Thanks to all those who emailed me or left comments letting me know that this could be done using other means. As things go with R, it's sometimes ...

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