1742 search results for "GIS"

RUG Introduction: Los Angeles area R Users Group

July 28, 2010
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RUG Introduction: Los Angeles area R Users Group

A nice group of people from academia and industry meeting about once a month at UCLA. Attendance is usually 30-40, but gradually increasing (also about 300 registered members). If you’d like to join, visit the group’s website: http://www.meetup.com/LAarea-R-usergroup/, you’ll find … Continue reading

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Hadley Wickham’s ggplot2 / Data Visualization Course Materials

July 27, 2010
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Hadley Wickham, creator of ggplot2, an immensely popular framework for Tufte-friendly data visualization using R, is teaching two short courses at Vanderbilt this week. Once we opened registration to Vanderbilt students and staff we instantly filled al...

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Mystery solved: The discrepancy in homicide data

July 27, 2010
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Mystery solved: The discrepancy in homicide data

I've been complaining about how homicide statistics from police sources were too low in 2009, with the entire state of Chihuahua having less homicides than its biggest city. I was thinking of finding out if I could use the IFAI (Freedom of Information Access) to obtain the original CIEISP forms which the state police forces are supposed to fill out each month...

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Mystery solved: The discrepancy in homicide data

July 27, 2010
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Mystery solved: The discrepancy in homicide data

I've been complaining about how homicide statistics from police sources were too low in 2009, with the entire state of Chihuahua having less homicides than its biggest city. I was thinking of finding out if I could use the IFAI (Freedom of Information Access) to obtain the original CIEISP forms which the state police forces are supposed to fill out each month...

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Extracting Raster Values from Points in R and GRASS

July 26, 2010
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A common task in GIS analysis is to extract the value of a remotely sensed environmental variable at a point location. For instance we may wish to extract the elevation of a field plot from a digital elevation model. The elevation data is a raster (i.e. grid) and the plots are a point shapefile (or a simple text file of X,...

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Extracting Raster Values from Points in R and GRASS

July 26, 2010
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A common task in GIS analysis is to extract the value of a remotely sensed environmental variable at a point location. For instance we may wish to extract the elevation of a field plot from a digital elevation model. The elevation data is a raster (i.e. grid) and the plots are a point shapefile (or a simple text file of X,...

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R Plotting tips

July 26, 2010
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Yes...I haven't been updating the blog for a very long while...But I'm really busy with many things right know.... Our paper for the "Cultural Evolution in Spatially Structured Populations" have been accepted so we are currently working on that, and I ...

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R Plotting tips

July 26, 2010
By

Yes...I haven't been updating the blog for a very long while...But I'm really busy with many things right know.... Our paper for the "Cultural Evolution in Spatially Structured Populations" have been accepted so we are currently working on that, and I ...

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Installing rgdal on Mac OS X

July 23, 2010
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The rgdal package contains bindings from R to the GDAL (Geospatial Data Abstraction Library) as well as the PROJ library. It is a dependency for numerous spatial statistics packages. Note that the binaries on the rgdal homepage are outdated — the most up-to-date version of the rgdal package can be found on CRAN. Unsurprisingly, rgdal

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Cherry Picking to Generalize ~ retrospective meta-power analysis using Cohen’s f^2 of NASA temp + visualization

July 17, 2010
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Cherry Picking to Generalize ~ retrospective meta-power analysis using Cohen’s f^2 of NASA temp + visualization

Previously, I plotted a grid of NASA GISS global temps in ggplot2 to show general trends by the brute force method. Here, I will again use the brute force method to do a simple power analysis on a portion of the data (data here). The general aim is to figure out what the minimum sample

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