Tag Archives: chladni

More on Toeplitz Matrices and Tree Ring Networks

Mar 23, 2008 – 8:50 AM

Yesterday’s results connecting eigenvector patterns in the Stahle SWM network to Toeplitz matrices and spatial autocorrelation were obviously pretty interesting. Needless to say, I was interested to test these ideas on out some other networks and see how they held up. There is a large literature on spatial autocorrelation and there appear to be well-known […]

By Stephen McIntyre | Posted in chladni, General | Also tagged , , | Comments (41)

Toeplitz Matrices and the Stahle Tree Ring Network

Mar 22, 2008 – 7:48 AM

One of the most ridiculous aspects and most misleading aspects of MBH (and efforts to rehabilitate it) is the assumption that principal components applied to geographically heterogeneous networks necessarily yield time series of climatic interest. Preisendorfer (and others) state explicitly that principal components should be used as an exploratory method – and disavowed any notion […]

By Stephen McIntyre | Posted in chladni, Data, Multivariate, Proxies | Also tagged , | Comments (27)

Bilge in Tamino's Canoe

Mar 17, 2008 – 10:03 PM

In order to illustrate a useful application of principal components, Tamino showed coordinate systems for the motion of a canoe. In the context of MBH, it would have been more instructive to show how principal components apply to tree ring networks than to canoes. In such a context,a non-Mannian centered PC1 will typically show some […]

By Stephen McIntyre | Posted in General | Also tagged | Comments (29)

Principal Components and Tree Ring Networks

Mar 17, 2008 – 12:26 PM

I’m finding some benefit to having spent some time on station histories prior to my present re-visit to Mannian proxies. Digging into the handling of station histories gives some interesting perspectives on network handling that are worth considering for tree ring networks. For example, assume for a moment that North American tree ring chronologies used […]

By Stephen McIntyre | Posted in General | Also tagged | Comments (62)