Package 'MASS' (polr): Error in svd(X) : infinite or missing values in 'x'
Hi Jeremy, I think Jessica is right that probably you could make polr converge and produce a Hessian if the data are better scaled, but there might also be other things not allowing you to get the Hessian/vcov. Could be insightful if you showed us the result of str(Jdata) Also, I am thinking that perhaps the another implementation of ordinal regression models might avoid the problem. You could try the ordinal package (of which I am the author) -- the following should reproduce the MASS::polr results: install.packages(ordinal) library(ordinal) Global <- clm(JVeg5 ~ Elevation + Lat_Y_pos + Coast_dist + Stream_dist, data=Jdata) summary(Global) Another option would be Frank Harrell's lrm function in the rms package. HTH, Rune
On 9 July 2012 11:55, Jeremy Little <jeremy.little at my.jcu.edu.au> wrote:
Hello, I am trying to run an ordinal logistic regression (polr) using the package 'MASS'. I have successfully run other regression classes (glm, multinom) without much problem, but with the 'polr' class I get the following error: " Error in svd(X) : infinite or missing values in 'x' " which appears when I run the "summary" command. The data file is large (585000 rows) and has no NA, -9999 or blank values. My script (in brief) is as follows, with results: ############
library(MASS)
## ADD DATA
Jdata<- read.delim("/Analysis/20120709 JLittle data file.txt", header=T)
attach(Jdata)
names(Jdata)
[1] "POINTID" "Lat_Y_pos" "JVeg5" "Subregion" "Rock_U_Nam" "Rock_Name" "Elevation" "Slope" "Aspect" "Hillshade" "Stream_dist" "Coast_dist" "Coast_SE" [14] "Coast_E" "Wind_310" "TPI" "Landform"
Global <- polr(JVeg5 ~ Elevation + Lat_Y_pos + Coast_dist + Stream_dist, data=Jdata) summary(Global)
Error in svd(X) : infinite or missing values in 'x'
##Try with omit NA command
Global <- polr(JVeg5 ~ Elevation + Lat_Y_pos + Coast_dist + Stream_dist, data=Jdata, na.action = na.omit, Hess = TRUE) summary(Global)
Error in svd(X) : infinite or missing values in 'x' ############ Does this imply an 'infinite value' and what would this mean? If anyone has any idea how to address this error, I would very much appreciate your response. Thank you in advance. Jeremy Date File Attachment (200 rows): http://r.789695.n4.nabble.com/file/n4635829/20120709_JLittle_data_file.txt 20120709_JLittle_data_file.txt -- View this message in context: http://r.789695.n4.nabble.com/Package-MASS-polr-Error-in-svd-X-infinite-or-missing-values-in-x-tp4635829.html Sent from the R help mailing list archive at Nabble.com.
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Rune Haubo Bojesen Christensen Ph.D. Student, M.Sc. Eng. Phone: (+45) 45 25 33 63 Mobile: (+45) 30 26 45 54 DTU Informatics, Section for Statistics Technical University of Denmark, Build. 305, Room 122, DK-2800 Kgs. Lyngby, Denmark