3051 search results for "GIS"

Simulation shows gain of clmm over ANOVA is small

May 5, 2013
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Simulation shows gain of clmm over ANOVA is small

After last post's setting up for a simulation, it is now time to look how the models compare. To my disappointment with my simple simulations of assessors behavior the gain is minimal. Unfortunately, the simulation took much more time than I ...

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Do Torontonians Want a New Casino? Survey Analysis Part 1

May 2, 2013
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Do Torontonians Want a New Casino?  Survey Analysis Part 1

Toronto City Council is in the midst of a very lengthy process of considering whether or not to allow the OLG to build of a new casino in Toronto, and where.  The process started in November of 2012, and set … Continue reading →

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TV shows rated by episode as a Shiny App

May 1, 2013
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TV shows rated by episode as a Shiny App

A few days ago there was an interesting R based article by diffuseprior on the decline and fall in the quality of The Simpsons The author scraped results from GEOS, an online survey of TV programs, and applied the R package changepoint to offer an analysis of the show over time This seemed a candidate

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A pathological glm() problem that doesn’t issue a warning

May 1, 2013
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A pathological glm() problem that doesn’t issue a warning

I know I have already written a lot about technicalities in logistic regression (see for example: How robust is logistic regression? and Newton-Raphson can compute an average). But I just ran into a simple case where R‘s glm() implementation of logistic regression seems to fail without issuing a warning message. Yes the data is a Related posts:

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Integrating Documentation and Calculation

April 30, 2013
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Integrating Documentation and Calculation Integrating Documentation and Calculation This post is a first in that I've authored it using RStudio. I would guess most people who work in computational finance or quantitative risk are at least familiar with R. Unfortunately R as...

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SAS Big Data Analytics Benchmark (Part One)

April 30, 2013
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by Thomas Dinsmore On April 26, SAS published on its website an undated Technical Paper entitled Big Data Analytics: Benchmarking SAS, R and Mahout. In the paper, the authors (Allison J. Ames, Ralph Abbey and Wayne Thompson) describe a recent project to compare model quality, product completeness and ease of use for two SAS products together with open source...

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A Brief Tour of the Trees and Forests

April 29, 2013
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A Brief Tour of the Trees and Forests

Tree methods such as CART (classification and regression trees) can be used as alternatives to logistic regression. It is a way that can be used to show the probability of being in any hierarchical group. The following is a compilation of many of the key R packages that cover trees and forests.  The goal here

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Poor man’s integration – a simulated visualization approach

April 29, 2013
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Poor man’s integration – a simulated visualization approach

Every once in a while I encounter a problem that requires the use of calculus. This can be quite bothersome since my brain has refused over the years to retain any useful information related to calculus. Most of my formal training in the dark arts was completed in high school and has not been covered

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Webinar May 1: What’s new in Revolution R Enterprise 6.2

April 29, 2013
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Revolution R Enterprise 6.2 is now available, and includes many new features that enhance the performance, scalability and enterprise readiness of R. On May 1, product manager Thomas Dinsmore will give an overview of the new features in a 30-minute webinar. You can register for the webinar (and the post-webinar slides and replay) at the link below. Revolution Analytics...

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Editing/Adding factor levels in R

April 29, 2013
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I was trying to change few levels in my factor variable by simply coercing characters on that factor variable but it dint seem to work. data(iris)iris$Species <- rep("Random", 71) ## Warning: invalid factor level, NAs generated iris$Species ## setosa ...

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