Aquarius
2011-Jun-25 01:28 UTC
[R] Error in qr.solve(crossprod(xsar), t(xsar)) when using SpatialFiltering
I am using the R function SpatialFiltering to my land value dataset. I compute a 500 by 500 binary spatial weight matrix (W) based on the x and y coordinates in my land value dataset. The nearest 6 neighbours were given a value of 1. By construction Wii=0. So my weight matrix look like 0 ..1 0 0 ... 1 0 0......1.....0... ....0...1...... # of rows= 500. # of columns =500. Row sum =6 (because of nearest neighbour=6) Then I fed the data into the SpatialFiltering fxn: tmp = mat2listw(wt); results= SpatialFiltering(LandValue ~ 1+AI+Area_SF_08+Dist2CBD05, data=lu2, nb=tmp$neighbours, style="W", ExactEV=TRUE, zero.policy=TRUE) %%%%%%%%%%%%%%%%%%% Then an error message occur: Error in qr.solve(crossprod(xsar), t(xsar)) : singular matrix 'a' in solve Can someone help me out? Thank you so much in advance! Yiyi -- View this message in context: http://r.789695.n4.nabble.com/Error-in-qr-solve-crossprod-xsar-t-xsar-when-using-SpatialFiltering-tp3623943p3623943.html Sent from the R help mailing list archive at Nabble.com.