2676 search results for "GIS"

JSM 2010 [day 1]

August 2, 2010
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JSM 2010 [day 1]

The first day at JSM is always a bit sluggish, as people slowly drip in and get their bearings. Similar to last year in Washington D.C., the meeting takes place in a huge conference centre and thus there is no feeling of overcrowded . It may also be that the peripheric and foreign location

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How to install R packages from source on Mac OS X

July 31, 2010
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In my last post about installing the rgdal R package on Mac OS X, I had apparently glossed over the last step of compiling the R package from source.  I hadn’t realized that Mac OS X actually doesn’t come default with the necessary software to do this.  Most times, prepackaged binaries work fine but occasionally,

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Using Optmatch and RItools for Observational Studies

July 29, 2010
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Using Optmatch and RItools for Observational Studies

I am a contributor to the optmatch and the RItools packages for R. These two packages are separate, but complimentary. Both packages provide tools for adjusting observational data to exhibit “balance” on observed covariates. In a randomized control trial, treatment and control groups should have identical distributions over all covariates, observed and unobserved. Matching provides a...

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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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