# 1511 search results for "regression"

## The guts of a statistical factor model

November 12, 2012
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Specifics of statistical factor models and of a particular implementation of them. Previously Posts that are background for this one include: Three things factor models do Factor models of variance in finance The BurStFin R package The quality of variance matrix estimation The problem Someone asked me some questions about the statistical factor model in … Continue reading...

## Exploring GAMs with Rosemary Hartman

November 9, 2012
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Today at Davis R Users’ Group, Rosemary Hartman took us through her work in progress fitting general additive models to organism presence/absence data. Below is her presentation and script. You can get the original script and data here Also, check the comments below for some discussion of other options for this type of analysis, such as...

## Terrain effects on SUHI estimates

November 9, 2012
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Introduction Zhang and Imhoff (2010)  pdf here utilized NLCD impervious surface area (ISA), Olson biomes, and MODIS Land Surface temperature (LST) to estimate the magnitude of UHI in large cities across the US.  Peng  employed a   similar approach in studying 419 large cities ( population greater than 1m ) around world. Peng’s work suggests a limit or

November 8, 2012
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Last week I talked about objects including scalars, vectors, matrices, dataframes, and lists.  This post will show you how to use the objects (and their corresponding classes) you create in R to your advantage.First off, it's important to remember...

## What’s new in Revolution R Enterprise 6.1

November 8, 2012
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We're pleased to announce that the latest update to Revolution R Enterprise is available today! Existing subscribers will soon receive an email with update instructions, and the free academic distribution will be updated later today. Version 6.1 adds a frequently-requested big-data statistical modeling algorithm, adds new connectivity option for Hadoop, improves performance, and provides new security and installation options...

## In case you missed it: October 2012 Roundup

November 7, 2012
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In case you missed them, here are some articles from October of particular interest to R users. Sponsorships for local R user groups from Revolution Analytics are now open to applicants worldwide. During the landfall of Hurricane Sandy in the US, several R-based apps used public weather and social media data to document its impact, like this timeline of...

## Webinar Thursday: How R is used to optimize tractor production at John Deere

November 6, 2012
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I just sat in on the rehearsal for Thursday's webinar by John Deere's Derek Hoffman, Order Fulfillment Forecasting at John Deere: How R Facilitates Creativity and Flexibility. Derek will give a spirited argument of why R is critical for the faming equipment manufacturer's operations: from forecasting demand for equipment, forecasting crop yields (they produce forecasts for more than half...

## Multi-stage sampling together with hierarchical/ mixed effects models: which packages?

November 5, 2012
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Dear R experts, I sent this question to the r-help list but didn’t get much response, probably because it is more of a stats question. But as this blog is syndicated on r-bloggers I thought I would try it again here on this blog. If I am barking up the wrong tree, feel free to

## Unstable parallel simulation, or after finishing testing, test some more

November 2, 2012
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Lately I have been working on a trading system based on Support Vector Machine (SVM) regression (and yes, if you wonder, there are a few posts planned to share the results). In this post however I want to share an interesting problem I had to deal with. Few days ago, I started running simulations using

## Why pictures are so important when modeling data?

October 31, 2012
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$R^2$

(bis repetita) Consider the following regression summary,Call: lm(formula = y1 ~ x1)   Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 3.0001 1.1247 2.667 0.02573 * x1 0.5001 0.1179 4.241 0.00217 **...