1928 search results for "time series"

JAGS and Stan

August 24, 2014
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JAGS and Stan

During the last year I have been running some estimations in both JAGS and Stan. In that period I have seen one example where JAGS could not get me decent samples (in the sense of low Rhat and high number of effective samples) but that was data which I...

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Extracting Latent Variables from Rating Scales: Factor Analysis vs. Nonnegative Matrix Factorization

August 21, 2014
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Extracting Latent Variables from Rating Scales: Factor Analysis vs. Nonnegative Matrix Factorization

For many of us, factor analysis provides a gateway to learning how to run and interpret nonnegative matrix factorization (NMF). This post will analyze a set of ratings on a 218 item adjective checklist using both principal axis factor analysis and NMF....

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Quantitative Finance applications in R – 8

August 12, 2014
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Quantitative Finance applications in R – 8

The latest in a series by Daniel Hanson Introduction Correlations between holdings in a portfolio are of course a key component in financial risk management. Borrowing a tool common in fields such as bioinformatics and genetics, we will look at how to use heat maps in R for visualizing correlations among financial returns, and examine behavior in both a...

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Exploiting Heterogeneity to Reveal Consumer Preference: Data Matrix Factorization

August 11, 2014
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Exploiting Heterogeneity to Reveal Consumer Preference: Data Matrix Factorization

We begin with a data matrix, a set of numbers arrayed so that each row contains information from a different consumer. Marketing research focuses on the consumer, but the columns are permitted more freedom, although they ought to tell us something abou...

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What your twitter friends say about you and your interests

August 10, 2014
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What your twitter friends say about you and your interests

This post is first in a series that looks at the inferences you can make using social media data. The …Continue reading →

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Guns are Cool – Differences between states

August 3, 2014
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Guns are Cool – Differences between states

Last week my blog showed that there are differences between states in the shootingtracker database. This week it is attempted to understand why states are different. A number of variables were extracted from a few sources, among which gun laws, % ...

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qdap 2.1.1 Released

August 2, 2014
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qdap 2.1.1 Released

We’re very pleased to announce the release of qdap 2.1.1 This is the latest installment of the qdap package available at CRAN. Several important updates have occurred since we last blogged about the 1.3.1 release (demoing Version 1.3.1), most notable: … Continue reading →

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Measuring Fat Loss without the scale

July 30, 2014
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Measuring Fat Loss without the scale

@tdhopper posted his self-measurements of weight loss a few months back. I recently decided also that I wanted to lose fat-weight—the infamous “I could stand to be a few kilos lighter”—and I think I came up with a more productive way of thinking about my progress: I’m not going to look at the scale at all....

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Packages vs ProjectTemplate

Packages vs ProjectTemplate tl;dr Imposing a different structure than R packages for distributing R code is a bad idea, especially now that R package tools have gotten to the point where managing a package has become much easier. ProjectTemplate ?? My last two posts (1, 2) provided an argument and an example of why one should use R packages to contain...

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Revisiting package dependencies

July 29, 2014
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Revisiting package dependencies

by Andrie de Vries In my previous post I wrote about how to identify and visualize package dependencies. Within hours, Duncan Murdoch (member of R-core) identified some discrepancies between my list of dependencies and the visualisation. Since then, I fixed the dispecrancies. In this blog post I attempt to clarify the issues involved in listing package dependencies. In miniCRAN...

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