2151 search results for "MAP"

In case you missed it: March Roundup

April 14, 2011
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In case you missed them, here are some articles from February of particular interest to R users. The doSMP package, which enables parallel processing for R on multiprocessor machines, is now available on CRAN. The Offensive Politics blog provided R code used to make a map of precinct returns in the Chicago mayoral election. A connector to integrate R...

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Measuring Price Dispersion of Marijuana

April 12, 2011
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Measuring Price Dispersion of Marijuana

The intersection of mapping APIs, fast database operations and user engagement offers a lot of very cool crowdsourcing applications ranging from the benign and powerful (Google’s Person Finder) to the minor and questionable (A DUI checkpoints app). Most intriguing in … Continue reading →

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Using R + Bioconductor to Get Flanking Sequence Given Genomic Coordinates

April 12, 2011
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I'm working on a project using next-gen sequencing to fine-map a genetic association in a gene region. Now that I've sequenced the region in a small sample, I'm picking SNPs to genotype in a larger sample. When designing the genotyping assay the lab wi...

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Using R + Bioconductor to Get Flanking Sequence Given Genomic Coordinates

April 12, 2011
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Using R + Bioconductor to Get Flanking Sequence Given Genomic Coordinates

I'm working on a project using next-gen sequencing to fine-map a genetic association in a gene region. Now that I've sequenced the region in a small sample, I'm picking SNPs to genotype in a larger sample. When designing the genotyping assay the lab wi...

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Quality comparison of floating-point maths libraries

April 10, 2011
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Quality comparison of floating-point maths libraries

What is the best way to compare the quality of floating-point math libraries (e.g., sin, cos and log)? The traditional approach for evaluating the quality of an algorithm implementing a mathematical function is based on mathematics; methods have been developed to calculate the maximum error between the calculated and the actual value. The answer produced

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How did I make this plot?

April 9, 2011
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How did I make this plot?

To make this plot, I used R's plot(), points() and lines() commands. If you have been wanting to learn how to plot in R, watch it unfold in this video tutorial:Also, here's the code I used:

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How to Shade Under a Normal Density in R

April 3, 2011
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How to Shade Under a Normal Density in R

The easiest-to-find method for shading under a normal density is to use the polygon() command. That link is to the first hit on Google for "Shading Under a Normal Curve in R." It works (like a charm), but it is not the most intuitive way to let users p...

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Interestingness Measures

Interestingness Measures

Probably because I first encountered them somewhat late in my professional life, I am fascinated by categorical data types.  Without question, my favorite book on the subject is Alan Agresti’s Categorical Data Analysis (Wiley Series in Probabili...

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How to Bootstrap in R: The Case of R-squared

March 29, 2011
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How to Bootstrap in R: The Case of R-squared

I recorded a new video tutorial whose original intent was to demonstrate how to write a for loop. As I wanted to make the for loop count for something, I decided that my application would be to write some code that computes the bootstrap approximation ...

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Prune GWAS data in R

March 29, 2011
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Prune GWAS data in R

Hansong Wang, our biostats professor here at the Hawaii Cancer Center, generously gave me some R code that goes through a SNP annotation file (i.e. a mapfile) and selects SNPs that are at least a certain specified distance apart. You might want to do t...

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