1539 search results for "regression"

Risk, Return and Analyst Ratings

October 7, 2011
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Risk, Return and Analyst Ratings

Today I want to discuss a connection between Risk, Return and Analyst Ratings. Let’s start with defining our universe of stocks : 30 stocks from Dow Jones Industrial Average (^DJI) index. For each stock I will compute the number of Upgrades and Downgrades, Risk, and Return in 2010:2011. I will run a linear regression and

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All combinations for levelplot

October 7, 2011
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All combinations for levelplot

In a previous post I explained how to create all possible combinations of the levels of two factors using expand.grid(). Another use for this function is to create a regular grid for two variables to create a levelplot or a … Continue reading →

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Assumptions of the Linear Model

October 6, 2011
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Assumptions of the Linear Model

Linear Assumptions from the Analysis Factor – Assumptions of linear regression (and ANOVA) are about the residuals, not the normality or independence of the response variable (Y). If you don’t know what this means be sure to read this brief … Continue reading →

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Modelling with R: part 3

October 5, 2011
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The previous posts, part 1 and part 2, detailed the procedure to successfully import the data and transform the data so that we can extract some useful information from them. Now it's time to get our hands dirty with some predictive modelling. The dependent variable here is a binary variable taking values "0" and "1", indicating whether the customer...

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Drawing maps using shapefiles and R

October 4, 2011
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Drawing maps using shapefiles and R

Sometimes a student may use a self explained chart, instead of a boring table for showing outcomes in a research paper. Yet, graphs are efficient in showing the broad picture of an issue and also for present results. In political science, you can getting into this topic reading Kastellec and Leoni (2007), for instance. I

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GEE using Stata vs. R

October 4, 2011
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I am running GEE logistic regression model for my fetal loss paper. As usual, I compare results between Stata and R and make sure they are consistent. To my surprise, the models assuming independent correlation structure give similar results but the mo...

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Bayesian Computation with R – Albert (2009)

October 4, 2011
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Bayesian Computation with R – Albert (2009)

Title: Bayesian Computation with RAuthor(s): Jim AlbertPublisher/Date: Springer/2009Statistics level: High Programming level: Low Overall recommendation: Recommended Bayesian Computation with R focuses primarily on providing the reader with a basic understanding of Bayesian thinking and the relevant analytic tools included in R. It does not explore either of those areas in detail, though it does hit The post Bayesian...

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permute: a package for generating restricted permutations

October 4, 2011
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permute: a package for generating restricted permutations

Multivariate ordination methods are commonly used in ecology to investigate patterns in species composition in space or time. Constrained ordination methods such as redundancy analysis (RDA) and canonical correspondence analysis (CCA) are effectively just multiple regressions, but we lack the … Continue reading →

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Example 9.8: New stuff in SAS 9.3– Bayesian random effects models in Proc MCMC

October 4, 2011
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Example 9.8: New stuff in SAS 9.3– Bayesian random effects models in Proc MCMC

Rounding off our reports on major new developments in SAS 9.3, today we'll talk about proc mcmc and the random statement.Stand-alone packages for fitting very general Bayesian models using Markov chain Monte Carlo (MCMC) methods have been available for...

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permute: a package for generating restricted permutations

October 4, 2011
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permute: a package for generating restricted permutations

Multivariate ordination methods are commonly used in ecology to investigate patterns in species composition in space or time. Constrained ordination methods such as redundancy analysis (RDA) and canonical correspondence analysis (CCA) are effectively just multiple regressions, but we lack the parametric theory to adequately test the statistical significance of terms in the model. Other techniques likewise lack the appropriate...

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