I'm trying to specify a model using lmer with a binary response and
interaction term, but I get an error I can't parse (see below).
Here is some sample data:
Subject Concord Age Disc
SVC999MX148SU-F yes u int
TOU999JU030S1 yes u int
TOU999JU030S1 yes u int
TOU999JU030S1 yes u int
TUT578MX037S2 yes g int
COL140MX114S2 yes yf mix
COL140MX114S6 yes u mix
COL140MX114S2 yes yf mix
COL425MX075S2 yes of mix
COL425MX075S2 yes of mix
COL425MX075S2 yes of mix
STP560JG118S14 no g pnl
STP560JG118S22 no g pnl
STP560JG118S20 no g pnl
STP560JG118S15 no g pnl
STP560JG118S20 no g int
And here is the model:
lmer_int_ageXdisc <- lmer(Concord ~ Age*Disc
+ (1|Subject), family="binomial", data=d, method="Laplace")
In the actual data set the AgexDisc interaction should have 16 levels.
This produces the error:
Error in devLaplace(PQLpars) : Leading minor of order 7 in downdated X'X is
not positive definite
What does this mean? This error is not thrown for other interactions I
specify from my data.
Here is my session info:
R version 2.4.1 (2006-12-18)
i386-pc-mingw32
locale:
LC_COLLATE=English_United States.1252;LC_CTYPE=English_United
States.1252;LC_MONETARY=English_United
States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252
attached base packages:
[1] "stats" "graphics" "grDevices" "utils" "datasets" "methods"
[7] "base"
other attached packages:
lme4 Matrix lattice
"0.9975-13" "0.9975-11" "0.14-17"
Thanks in advance for your help!
--
Brian Riordan
NICHD Postdoctoral Fellow
Psychological and Brain Sciences
Indiana University
[[alternative HTML version deleted]]
______________________________________________
[email protected] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
