[Read more...]

It's a Deeply Trivial first - I made my first video! In it, I talk through conducting and interpreting the output of the analyses from the F is for (Confirmatory) Factor Analysis post.Also referenced in the video:Goodness of Fit post - a reminder of ho... [Read more...]

In the Beta post, I used linear regression and demonstrated how to request standardized regression coefficients (betas). You may remember that I mentioned in that post that there are other types of regression. Linear regression is used with a continouous outcome. But sometimes you want to predict outcomes that aren't ... [Read more...]

Soil survey data are typically built upon a foundation of soil-landscape relationships that have been verified in the field. SSURGO data contain several geomorphic descriptions of landscape, landform, hillslope position, and surface shape for each... [Read more...]

[Read more...]

UPDATED 2013-04-08 This functionality it now available in the soilDB and sharpshootR packages. All code on this page is now superseded by the fetchOSD() and SoilTaxonomyDendrogram()functions. UPDATED 2012-11-07 I have been thinking about a URL-ba... [Read more...]

R provides several frameworks for composing figures. Base graphics is the simplest, grid is more advanced, and the lattice/ggplot packages provide convenient abstractions of the grid graphics system. Multi-element figures can be readily created in... [Read more...]

Here is a quick demonstration of how functionality from the AQP package can be used to answer complex soils-related questions. In these examples the profileApply() function is used to iterate over a collection of soil profiles, and compute severa... [Read more...]