problem predicting with re.form

[bbolker]

From StackOverflow

Dataone <- read.csv2("Dataone.csv")
library(lme4)
ModLMER = lmer(Var1~I(Var2)+I(Var2^2)+(1|Var3)+(0+dummy(Var4,"1")|Var5),
                Dataone, REML = TRUE,
                control=lmerControl(check.nobs.vs.nlev="ignore",
                check.nobs.vs.nRE="ignore"))
## attempt to predict excluding dummy term
predict(ModLMER, re.form = ~1|Var3)

Error in contrasts<-(*tmp*, value = contr.funs[1 + isOF[nn]]) :
contrasts can be applied only to factors with 2 or more levels

Dataone.csv

[bdeonovic]

@bbolker Here is another one (with slighly simpler structure) with a slightly different error:

dfo <- read.csv("test.csv")
m1 <- lmer(
            yield ~ lc +
                (1 | g1) +
                (1 | g2) +
                (lc | g3),
            data = dfo
        )
     predict(m1, re.form = ~(1|g1))

Error in `contrasts<-`(`*tmp*`, value = orig.random.cntr[[fn]]) : 
  contrasts can be applied only to factors with 2 or more levels

test.csv

package version info:

r$> sessionInfo()
R version 4.2.3 (2023-03-15)
Platform: aarch64-apple-darwin20 (64-bit)
Running under: macOS Ventura 13.6.4

Matrix products: default
LAPACK: /Library/Frameworks/R.framework/Versions/4.2-arm64/Resources/lib/libRlapack.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] marginaleffects_0.12.0 ggbeeswarm_0.7.2       lme4_1.1-33            Matrix_1.5-3           readxl_1.4.2           here_1.0.1             lubridate_1.9.2        forcats_1.0.0         
 [9] stringr_1.5.0          dplyr_1.1.1            purrr_1.0.1            readr_2.1.4            tidyr_1.3.0            tibble_3.2.1           ggplot2_3.4.4          tidyverse_2.0.0       

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.12       vipor_0.4.5       nloptr_2.0.3      pillar_1.9.0      compiler_4.2.3    cellranger_1.1.0  tools_4.2.3       boot_1.3-28.1     nlme_3.1-162      jsonlite_1.8.8   
[11] lifecycle_1.0.4   gtable_0.3.4      timechange_0.2.0  lattice_0.20-45   pkgconfig_2.0.3   rlang_1.1.3       cli_3.6.2         beeswarm_0.4.0    withr_3.0.0       generics_0.1.3   
[21] vctrs_0.6.5       hms_1.1.3         rprojroot_2.0.3   grid_4.2.3        tidyselect_1.2.0  data.table_1.14.8 glue_1.7.0        R6_2.5.1          fansi_1.0.6       minqa_1.2.5      
[31] tzdb_0.3.0        magrittr_2.0.3    MASS_7.3-58.2     splines_4.2.3     scales_1.3.0      colorspace_2.1-0  utf8_1.2.4        stringi_1.7.12    munsell_0.5.0