2223 search results for "Regression"

SAS PROC MCMC example in R: Logistic Regression Random-Effects Model

January 18, 2015
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In this post I will run SAS example Logistic Regression Random-Effects Model in four R based solutions; Jags, STAN, MCMCpack and LaplacesDemon. To quote the SAS manual: 'The data are taken from Crowder (1978). The Seeds data set is a 2 x 2 fa...

Introducing: Orthogonal Nonlinear Least-Squares Regression in R

January 17, 2015
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$Introducing: Orthogonal Nonlinear Least-Squares Regression in R$

With this post I want to introduce my newly bred ‘onls’ package which conducts Orthogonal Nonlinear Least-Squares Regression (ONLS): http://cran.r-project.org/web/packages/onls/index.html. Orthogonal nonlinear least squares (ONLS) is a not so frequently applied and maybe overlooked regression technique that comes into question when one encounters an “error in variables” problem. While classical nonlinear least squares (NLS) aims

Regression Solutions Available

January 8, 2015
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The github page for the APM exercises has been updated with three new files for Chapters 6-8 (the section on regression). The classifications section is in-progress. Here's one of our fancy-pants graphs:

Classification and Regression Trees using R

January 7, 2015
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Recursive partitioning is a fundamental tool in data mining. It helps us explore the structure of a set of data, while developing easy to visualize decision rules for predicting a categorical (classification tree) or continuous (regression tree) outcome. Classification and regression trees can be generated through the rpart package. The post Classification and Regression Trees using R appeared first on...

SAS PROC MCMC in R: Nonlinear Poisson Regression Models

December 6, 2014
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In exercise 61.1 the problem is that the model has bad mixing. In the SAS manual the mixing is demonstrated after which a modified distribution is used to fix the model.In this post the same problem is tackled in R; MCMCpack, RJags, RStan and LaplaceDemon. MCMCpack has quite some mixing problems, RStan seems to do best.DataTo quote the SAS...

Performing Logistic Regression in R and SAS

Introduction My statistics education focused a lot on normal linear least-squares regression, and I was even told by a professor in an introductory statistics class that 95% of statistical consulting can be done with knowledge learned up to and including a course in linear regression.  Unfortunately, that advice has turned out to vastly underestimate the

Interpreting regression coefficient in R

November 23, 2014
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Linear models are a very simple statistical techniques and is often (if not always) a useful start for more complex analysis. It is however not so straightforward to understand what the regression coefficient means even in the most simple case when there are no interactions in the model. If we are not only fishing for

SAS PROC MCMC example in R; Poisson Regression

November 16, 2014
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In this post I will try to copy the calculations of SAS's PROC MCMC example 61.5 (Poisson Regression) into the various R solutions. In this post Jags, RStan, MCMCpack, LaplacesDemon solutions are shown. Compared to the first post in this series, rcppbugs and mcmc are not used. Rcppbugs has no poisson distribution and while I know how to...

Iterative OLS Regression Using Gauss-Seidel

October 24, 2014
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I just finished covering a few numerical techniques for solving systems of equations, which can be applied to find best-fit lines through a give set of data points. The four points  are arranged into an inconsistent system of four equations and two unknowns: The system can be represented in matrix form: The least-squares solution vector can be … Continue reading...

October 19, 2014
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