3175 search results for "gis"

Searching Twitter with ArcGIS Pro Using R

August 18, 2015
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Searching Twitter with ArcGIS Pro Using R

I committed to testing this a long time ago, however, a number of other projects intervened, so I have only just got around to writing up this short tutorial. One of the exciting things from the ESRI Developers Conference this year was the launch of the R-ArcGIS bridge. In simple terms, this enables you to run R...

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Evaluating Logistic Regression Models

August 17, 2015
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Evaluating Logistic Regression Models

Logistic regression is a technique that is well suited for examining the relationship between a categorical response variable and one or more categorical or continuous predictor variables. The model is generally presented in the following format, where β refers to the parameters and x represents the independent variables. log(odds)=β0+β1∗x1+...+βn∗xn The log(odds), or log-odds ratio, is defined

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Empirical bias analysis of random effects predictions in linear and logistic mixed model regression

July 30, 2015
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Empirical bias analysis of random effects predictions in linear and logistic mixed model regression

In the first technical post in this series, I conducted a numerical investigation of the biasedness of random effect predictions in generalized linear mixed models (GLMM), such as the ones used in the Surgeon Scorecard, I decided to undertake two explorations: firstly, the behavior of these estimates as more and more data are gathered for each

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Roll Your Own Gist Comments Notifier in R

July 25, 2015
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As I was putting together the coord_proj ggplot2 extension I had posted a (https://gist.github.com/hrbrmstr/363e33f74e2972c93ca7) that I shared on Twitter. Said gist received a comment (several, in fact) and a bunch of us were painfully reminded of the fact that there is no built-in way to receive notifications from said comment activity. @jennybryan posited that it

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Logistic Growth, S Curves, Bifurcations, and Lyapunov Exponents in R

July 24, 2015
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Logistic Growth, S Curves, Bifurcations, and Lyapunov Exponents in R

If you’ve ever wondered how logistic population growth (the Verhulst model), S curves, the logistic map, bifurcation diagrams, sensitive dependence on initial conditions, “orbits”, deterministic chaos, and Lyapunov exponents are related to

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Hadley Wickham’s Master R Developer Workshop – Washington DC registration is open

June 12, 2015
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Hadley Wickham’s Master R Developer Workshop – Washington DC registration is open

“Master” R in Washington DC this September! Join RStudio Chief Data Scientist Hadley Wickham at the AMA – Executive Conference Center in Arlington, VA on September 14 and 15, 2015 for this rare opportunity to learn from one of the R community’s most popular and innovative authors and package developers. It will be at least another

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Simulation-based power analysis using proportional odds logistic regression

May 22, 2015
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Simulation-based power analysis using proportional odds logistic regression

Consider planning a clinicial trial where patients are randomized in permuted blocks of size four to either a 'control' or 'treatment' group. The outcome is measured on an 11-point ordinal scale (e.g., the numerical rating scale for pain). It may be reasonable to evaluate the results of this trial using a proportional odds cumulative logit

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R vs QGIS for sustainable transport planning

April 19, 2015
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R vs QGIS for sustainable transport planning

The 23rd iteration of the GIS Research UK conference (#GISRUK) conference was the largest ever. 250 researchers, industry representatives and academics attended from the vibrant geospatial research communities in the UK, Europe and beyond. GISRUK has become a centrepoint for discussion of new methods, software and applications in the field. I was on the organising committee, reviewed some excellent papers for the event (a full list...

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Registration Open for R/Finance 2015!

March 31, 2015
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You can find registration information and agenda details (as they become available) on the conference website.  Or you can go directly to the registration page.  Note that there's an early-bird registration deadl...

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R / Finance 2015 Open for Registration

March 31, 2015
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The annoucement below just went to the R-SIG-Finance list. More information is as usual at the R / Finance page. Registration for R/Finance 2015 is now open! The conference will take place on May 29 and 30, at UIC in Chicago. Building on the success of the previous conferences in 2009-2014, we expect more than 250 attendees from around...

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