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Checking for Spatial Clustering of Points in R

Posted by: admin 11 years, 6 months ago

The R script below tests whether a set of points on a plane is significantly clustered (as opposed to randomly distributed or, conversely, equally spaced), using the Clark-Evans R measure. From the R spatstat package manual "[Clark-Evans R] is the ratio of the observed mean nearest neighbour distance in the pattern to that expected for a Poisson point process of the same intensity. A value R>1 suggests ordering, while R<1 suggests clustering."

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Network Analysis of Large Online Datasets

Posted by: admin 11 years, 7 months ago

In late 2012, I spent an infinitely frustrating week trying to perform network analysis (specifically, build and run ergm models) on part of the bitcoin blockchain. I learned some things. If you are here because you want to run ergm models on large datasets, you're advised to back away slowly then run like hell. But here are some notes.

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