1632 search results for "time series"

Faster R through better BLAS

June 15, 2010
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Faster R through better BLAS

Can we make our analysis using the R statistical computing and analysis platform run faster? Usually the answer is yes, and the best way is to improve your algorithm and variable selection. But recently David Smith was suggesting that a big benefit of their (commercial) version of R...

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plagiarism exposed!

June 14, 2010
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plagiarism exposed!

Last morn, I had the surprise of receiving the following email: This is to inform you that the following abstract has been submitted to the 3rd International Conference of the ERCIM WG on COMPUTING & STATISTICS (ERCIM’10) Ab#: 114 Title: Goodness of Fit Via Mixtures of Beta distributions Keywords: nonparametric estimation, posterior conditional predictive p-value.

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Dynamic Modeling 3: When the first-order difference model doesn’t cut it

June 12, 2010
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Dynamic Modeling 3: When the first-order difference model doesn’t cut it

Data must be selected carefully.  The predictive usefulness of the model is grossly diminished if outliers taint the available data.  Figure 1, for instance, shows the Defense spending (as a fraction of the national budget) between 1948 and 1968. Note how the trend curve (as defined by our linear difference model from the last post: see

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biomaRt and GenomeGraphs: a worked example

June 6, 2010
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biomaRt and GenomeGraphs: a worked example

As promised a few posts ago, another demonstration of the excellent biomaRt package, this time in conjunction with GenomeGraphs. Here’s what we’re going to do: Grab some public microarray data Normalise and get a list of the most differentially-expressed probesets Use biomaRt to fetch the genes associated with those probesets Plot the data using GenomeGraphs

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MODIS processing with R, GDAL, and the NCO tools

June 3, 2010
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MODIS processing with R, GDAL, and the NCO tools

I use MODIS data for analysis of vegetation dynamics around the world.  The native HDF file format provided by NASA is great for archiving the data (it's amazing how much information they include in each file), but unfortunately there aren't many ...

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MODIS processing with R, GDAL, and the NCO tools

June 3, 2010
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MODIS processing with R, GDAL, and the NCO tools

I use MODIS data for analysis of vegetation dynamics around the world.  The native HDF file format provided by NASA is great for archiving the data (it's amazing how much information they include in each file), but unfortunately there aren't many tools for directly (and easily) extracting data stored across files like there are for the

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MODIS processing with R, GDAL, and the NCO tools

June 3, 2010
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MODIS processing with R, GDAL, and the NCO tools

I use MODIS data for analysis of vegetation dynamics around the world.  The native HDF file format provided by NASA is great for archiving the data (it's amazing how much information they include in each file), but unfortunately there aren't many tools for directly (and easily) extracting data stored across files like there are for the NetCDF format.  I...

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Betting on Pi

May 31, 2010
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Betting on Pi

I was reading over at math-blog.com about a concept called numeri ritardatari. This sounds a lot like “retarded numbers” in Italian, but apparently “retarded” here is used in the sense of “late” or “behind” and not in the short bus sense. I barely scanned the page, but I think I got the gist of it:

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Dynamic Modeling 2: Our First Substantive Model

May 30, 2010
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Dynamic Modeling 2: Our First Substantive Model

(This is the second of a series of ongoing posts on using Graph Algebra in the Social Sciences.) First-order linear difference equations are powerful, yet simple modeling tools.  They can provide access to useful substantive insights to real-world phenomena.  They can have powerful predictive ability when used appropriately.  Additionally, they may be classified in any number

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An XML Representation of the Keys to Soil Taxonomy?

May 28, 2010
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An XML Representation of the Keys to Soil Taxonomy?

Western Fresno Soil Hierarchy: partial view of the hierarchy within the US Soil Taxonomic system Maybe this is just craziness, but wouldn't be neat to have an XML formatted version of the Keys to Soil Taxonomy? The format might look something like the ...

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