We’ve had some server problems recently, so http://gwr.nuim.ie has been intermittent. This gave Chris Brunsdon and myself a chance to reflect on the nature of the website. A few changes are in hand.
We’re actually about the GWmodel R package, so we’ll change from Geographically Weighted Regression to Geographically Weighted Modelling in the not too distant future. The team that keeps all this in order is:
The Core Group
Chris Brunsdon: National Centre for Geocomputation, Maynooth University, Ireland
Martin Charlton: National Centre for Geocomputation, Maynooth University, Ireland
Paul Harris: Rothamsted Research, North Wyke, Devon, United Kingdom
Binbin Lu, School of Remote Sensing and Information Engineering, Wuhan University, China
Tomoki Nakaya, Department of Geography, Ritsumeikan University, Japan
They are assisted by a group of Associates:
Lex Comber, School of Geography, University of Leeds, United Kingdom
Richard Harris, School of Geographical Sciences, University of Bristol, United Kingdom
Guanpeng ‘Gavin’ Dong, Sheffield Methods Institute, University of Sheffield, United Kingdom
Check https://cran.r-project.org/web/packages/GWmodel/index.html regularly.
Chris Brunsdon and Martin Charlton attended the International Summer School on Spatial Structures and Dynamics, held at the Villa Finaly, Florence 14th-19th July 2014. Participants included 18 instructors together with 36 postgraduates and early career researchers. Chris presented the opening plenary, on Geocomputation and Social Science during the morning of Monday 14th July. In the afternoons of Monday and Tuesday we ran tutorials on Spatial Statistics to a smaller group of 18 students in each session. During each 3 hour tutorial the students were introduced to geographically weighted summary statistics, and geographically weighed regression, with an extensive practical based around GW summary statistics. The latest version of GWmodel and R was used for this, running on Mac and Windows laptops.
Participants in Monday afternoon’s tutorial
Participants in Tuesday afternoon’s tutorial
Chris presenting at the plenary on Monday morning.
The Summer school was organised by Arnoud Banos of the Laboratoire d’Excellence Dynamiques Territoriales et Spatiales (LabEx DynamiTe) which is part of the University of Paris 1 Sorbonne. There are some web pages about the workshop here; as well as some general information, there are photographs, videos, and some of the various presentations.
The Villa Finaly is a remarkable institution; originally built in the early 15th century, it was left to the Université de Paris in 1953 by the then owners, the Landau-Finaly family. In the 1990s the 13 Universities which now compose the Université de Paris, as common owners, decided to restore the building to something of its original splendour. More detail about the Villa is available.
An updated version of the GWR Windows application is now available for download. Version 4.08 incorporates a number of changes including: improvements to the fitting algorithm for Gaussian semiparametric models, some bug fixes, and a revision to the manual. Click on the GWR4 FOR WINDOWS link to find 32 bit and 64 bit versions of the software.
The Centre for Multilevel Modelling at the University of Bristol are hosting our forthcoming Geographically Weighted Modelling Workshop. The two day workshop will run on 23rd and 24th April 2014, and will be lead by Professor Chris Brunsdon, Dr Paul Harris and Martin Charlton. The workshop will be based around our GWmodel R package, and will cover geographically weighted versions of summary statistics, principal components analysis, and regression. Workshop attendees will need some familiarity with basic statistical concepts and techniques. While familiarity with the R statistical and visualisation software will be useful, it is not essential.
Places are limited; registration, which is essential, will close on 1st April 2014. Further details are to be found at the workshop page.
We have recently completed a couple of useful vignettes which should answer many of the questions we have had concerning the use of the GWmodel functions. Have a look at:
Gollini I, Lu B, Charlton M, Brunsdon C, Harris P (2013) GWmodel: an R Package for exploring Spatial Heterogeneity using Geographically Weighted Models, http://arxiv.org/abs/1306.0413
Lu B, Harris P, Charlton M, Brunsdon C (2013) The GWmodel R Package: further topics for exploring Spatial Heterogeneity using Geographically Weighted Models, http://arxiv-web3.library.cornell.edu/abs/1312.2753
to see if your question is covered.
Our new R package for Geographically Weighted Modelling, GWmodel, was recently uploaded to CRAN. GWmodel provides range of Geographically Weighted data analysis approaches within a single package, these include descriptive statistics, correlation, regression, general linear models and principal components analysis. The regression models include various for data with Gaussian, logistic and Poisson structures, as well as ridge regression for dealing with correlated predictors. A new feature of this package is the provision of robust versions of each technique – these are resistant to the effects of outliers.
Locations for modelling can be either in a projected coordinate system, or specified using geographical coordinates. Distance metrics include Euclidean, taxicab (Manhattan) and Minkowski, as well as Great Circle distances for locations specified by latitude/longitude coordinates. Various automatic calibration methods are also provided, and there are some helpful model building tools available to help select from alternative predictors.
Example datasets are also provided, and they are used in the accompanying documentation in illustrations of the use of the various techniques.
The documentation, with a description of the various functions, can be accessed at http://cran.r-project.org/web/packages/GWmodel/GWmodel.pdf.
We are currently working on another implementation of these functions as an ArcGIS Toolbox.
Martin Chartlton and Paul Harris
June 24th 2013