Ripley's K and its derivative, the L function, are widely used for detecting clusters over various spatial scales. The figure below is one of my favorites for illustrating the concept of a phenomenon displaying one spatial pattern over long distances, and another pattern over short distances. (Source) The genius of the K function is … Continue reading Ripley K
I just read Geoffrey Jacquez's (2008) paper on “Spatial Cluster Analysis”. Chapter 22 In “The Handbook of Geographic Information Science”, S. Fotheringham and J. Wilson (Eds.). Blackwell Publishing, pages 395-416. I enjoyed reading the paper for the simple fact that it points to a broad range of considerations that should enter into mainstream cluster analysis … Continue reading What else to do in Clusters Analyses?
Thanks to the pioneering efforts of ESRI, it is now relatively easy for GIS users to store their datasets in database software of all sorts. In this post, I present a short overview on storing GIS data in SQL Server Express. SQL Server Express is a free download from Microsoft. After installing it, make sure … Continue reading Loading Vector Data into SQL Express
Gentrification is the process of middle income people taking over older neighborhoods in central cities by purchasing homes, renovating them and changing the character of the neighborhoods completely. This process has been ongoing for decades and represents part of the back to the city movement of both capital and people in America, (Slater and Smith … Continue reading Modeling Gentrification
This week I read Michael Batty's (2001) paper on polynucleated urban landscape. Admittedly, the paper was published a long time ago, but the topic is still relevant as there is still a lot of interest in understanding the structure of system of urban places. Batty's paper essentially argues that the appearance of edge cities in … Continue reading Rank Size Rule and Polynucleated Cities
Agent- based modeling involves creating and giving instructions to different classes of virtual agents, then observing the patterns that emerge, in both time and space, as the agents interact with each other and with their environment over many runs. The emerging patterns offer insights into how a phenomenon might grow and change over time. Agent … Continue reading Agent Based Modeling
MapWinGIS.ocx is an open source mapping control that is used for adding GIS/mapping functionality to Windows Forms based applications. Code can be written in Visual Basic 6, VB .NET or C# and can be commercial or open source. If you ever thought about building your own custom GIS application, then MapWinGIS.ocx is a great tool … Continue reading MapWinGIS