2441 search results for "gis"

Technical Analysis of Montana Voter Registration Files

September 18, 2012
By
Technical Analysis of Montana Voter Registration Files

By Earl F Glynn | Franklin Center This article shows how to analyze Montana voter registration files using R. The Montana Secretary of State sells two files of voter registration records for a fee of $1000: Statewide Voter File Voter History File The Montana Secretary of State provides information about the two files on this

Read more »

How to embed a Gist in Tumblr

September 9, 2012
By

Here, both for the sake of posterity, as well as example, is an embedded Gist that describes how to embed a Gist in Tumblr: https://gist.github.com/1395926

Read more »

Virginia: Comparison of Registered Voter Counts to Census Voting Age Population

August 29, 2012
By
Virginia: Comparison of Registered Voter Counts to Census Voting Age Population

By Earl F Glynn | Franklin Center A comparison of US Census voting age population data in Virginia to voter registration data shows only one locality, Surry County, with about 100% of the voting age population registered to vote. Six other localities have about 95% of their voting age population registered:  Craig County, Isle of

Read more »

How robust is logistic regression?

August 23, 2012
By
How robust is logistic regression?

Logistic Regression is a popular and effective technique for modeling categorical outcomes as a function of both continuous and categorical variables. The question is: how robust is it? Or: how robust are the common implementations? (note: we are using robust in a more standard English sense of performs well for all inputs, not in theRelated posts:

Read more »

R for Ecologists: Putting Together a Piecewise Regression

August 19, 2012
By
R for Ecologists: Putting Together a Piecewise Regression

Piecewise regression comes about when you have ‘breakpoints’, where there are clearly two different linear relationships in the data with a sudden, sharp change in directionality. This crops up occasionally in ecology when dealing with, for example, species richness of understory plants … Continue reading →

Read more »

Missouri: Comparison of Registered Voter Counts to Census Voting Age Population

August 13, 2012
By
Missouri:  Comparison of Registered Voter Counts to Census Voting Age Population

By Earl F Glynn | Franklin Center A comparison of US Census voting age population data in Missouri to voter registration data shows a number of Missouri counties have bloated voter registration lists. Charts by county for the years 2000 to 2012 show how counties are maintaining their voter lists. Voter fraud potential is higher

Read more »

How to load the {rJava} package after the error “JAVA_HOME cannot be determined from the Registry”

August 7, 2012
By

In case you tried loading a package that depends on the {rJava} package (by Simon Urbanek), you might came across the following error: Loading required package: rJava library(rJava) Error : .onLoad failed in loadNamespace() for ‘rJava’, details: call: fun(libname, pkgname) …Read more »

Read more »

R for Ecologists: Simulating Species-Area Curves (linear vs. nonlinear regression)

August 7, 2012
By
R for Ecologists: Simulating Species-Area Curves (linear vs. nonlinear regression)

This post is about basic model simulation so we can get a feel for how curves are supposed to look given certain processes assumed by the model. One of the most prevalent patterns in ecology is the species-area (SAR) curve, which … Continue reading →

Read more »

R for Ecologists: Phylogenies in R

July 22, 2012
By
R for Ecologists: Phylogenies in R

I’ve only recently begun working from an evolutionary perspective, and I can’t imagine why I haven’t thought about it much before. After all, it comes up in just about everything that we do in ecology. For example, I’m currently feeding … Continue reading →

Read more »

R for Ecologists: Creating a Site x Species Matrix

July 17, 2012
By
R for Ecologists: Creating a Site x Species Matrix

Today I’m going to adress a fairly common problem in ecology that has been coming up frequently as of late. The issue is how to create a site x species matrix for community composition analysis (i.e. ordination). Moreover, ecologists have to do … Continue reading →

Read more »