Ok ! According to what I see, the error is occurring inside car:::Anova.lme(), specifically during the construction of the model matrix.
It therefore appears to be a genuine compatibility problem between the current CRAN versions of car (3.1-5), piecewiseSEM (2.3.1), and/or nlme (3.1-170). The fact that you reproduced the same behavior on both Windows and FreeBSD also suggests that the issue is not platform-specific. I think this would be worth reporting to the package maintainers (perhaps starting with car, since the traceback shows that the failure occurs inside Anova.lme(), while mentioning that the problem only arises after loading piecewiseSEM). The reproducible example you’ve provided should make it straightforward for them to investigate. > Le 19 juil. 2026 à 08:22, Jinsong Zhao <[email protected]> a écrit : > > Thank for the instruction. Here is the whole outputs: > > > library(piecewiseSEM) > Registered S3 method overwritten by 'lme4': > method from > na.action.merMod car > > This is piecewiseSEM version 2.3.0.2. > > > Questions or bugs can be addressed to <[email protected]>. > > library(nlme) > > library(car) > Loading required package: carData > > fm2 <- lme(distance ~ age + Sex, data = Orthodont, random = ~ 1) > > Anova(fm2) > Error in if (random) { : the condition has length > 1 > > car::Anova(fm2) > Error in if (random) { : the condition has length > 1 > > car:::Anova.lme(fm2) > Error in if (random) { : the condition has length > 1 > > traceback() > 8: model.frame.lme(object, data, xlev = xlev) > 7: model.frame(object, data, xlev = xlev) > 6: model.matrix.default(mod, data = structure(list(distance = c(26, > 25, 29, 31, 21.5, 22.5, 23, 26.5, 23, 22.5, 24, 27.5, 25.5, 27.5, > 26.5, 27, 20, 23.5, 22.5, 26, 24.5, 25.5, 27, 28.5, 22, 22, 24.5, > 26.5, 24, 21.5, 24.5, 25.5, 23, 20.5, 31, 26, 27.5, 28, 31, 31.5, > 23, 23, 23.5, 25, 21.5, 23.5, 24, 28, 17, 24.5, 26, 29.5, 22.5, > 25.5, 25.5, 26, 23, 24.5, 26, 30, 22, 21.5, 23.5, 25, 21, 20, > 21.5, 23, 21, 21.5, 24, 25.5, 20.5, 24, 24.5, 26, 23.5, 24.5, > 25, 26.5, 21.5, 23, 22.5, 23.5, 20, 21, 21, 22.5, 21.5, 22.5, > 23, 25, 23, 23, 23.5, 24, 20, 21, 22, 21.5, 16.5, 19, 19, 19.5, > 24.5, 25, 28, 28), age = c(8, 10, 12, 14, 8, 10, 12, 14, 8, 10, > 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, > 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, > 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, > 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, > 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, > 14, 8, 10, 12, 14, 8, 10, 12, 14, 8, 10, 12, 14), Subject = > structure(c(15L, > 15L, 15L, 15L, 3L, 3L, 3L, 3L, 7L, 7L, 7L, 7L, 14L, 14L, 14L, > 14L, 2L, 2L, 2L, 2L, 13L, 13L, 13L, 13L, 5L, 5L, 5L, 5L, 6L, > 6L, 6L, 6L, 11L, 11L, 11L, 11L, 16L, 16L, 16L, 16L, 4L, 4L, 4L, > 4L, 8L, 8L, 8L, 8L, 9L, 9L, 9L, 9L, 10L, 10L, 10L, 10L, 12L, > 12L, 12L, 12L, 1L, 1L, 1L, 1L, 20L, 20L, 20L, 20L, 23L, 23L, > 23L, 23L, 25L, 25L, 25L, 25L, 26L, 26L, 26L, 26L, 21L, 21L, 21L, > 21L, 19L, 19L, 19L, 19L, 22L, 22L, 22L, 22L, 24L, 24L, 24L, 24L, > 18L, 18L, 18L, 18L, 17L, 17L, 17L, 17L, 27L, 27L, 27L, 27L), levels = > c("M16", > "M05", "M02", "M11", "M07", "M08", "M03", "M12", "M13", "M14", > "M09", "M15", "M06", "M04", "M01", "M10", "F10", "F09", "F06", > "F01", "F05", "F07", "F02", "F08", "F03", "F04", "F11"), class = > c("ordered", > "factor")), Sex = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, > 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, > 2L, 2L, 2L, 2L), levels = c("Male", "Female"), class = "factor")), > row.names = c("1", > "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", > "14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", > "25", "26", "27", "28", "29", "30", "31", "32", "33", "34", "35", > "36", "37", "38", "39", "40", "41", "42", "43", "44", "45", "46", > "47", "48", "49", "50", "51", "52", "53", "54", "55", "56", "57", > "58", "59", "60", "61", "62", "63", "64", "65", "66", "67", "68", > "69", "70", "71", "72", "73", "74", "75", "76", "77", "78", "79", > "80", "81", "82", "83", "84", "85", "86", "87", "88", "89", "90", > "91", "92", "93", "94", "95", "96", "97", "98", "99", "100", > "101", "102", "103", "104", "105", "106", "107", "108"), outer = ~Sex, > class = c("nfnGroupedData", > "nfGroupedData", "groupedData", "data.frame"), formula = distance ~ > age | Subject, labels = list(x = "Age", y = "Distance from pituitary > to pterygomaxillary fissure"), units = list( > x = "(yr)", y = "(mm)"), FUN = structure(function (x) > max(x, na.rm = TRUE), source = "function (x) max(x, na.rm = TRUE)"), > order.groups = TRUE), > contrasts.arg = list(Sex = structure(c(0, 1), dim = 2:1, dimnames = > list( > c("Male", "Female"), "Female")))) > 5: NextMethod(formula(object), data = data, contrasts.arg = object$contrasts) > 4: model.matrix.lme(mod) > 3: model.matrix(mod) > 2: Anova_II_lme(mod, vcov., singular.ok = singular.ok) > 1: car:::Anova.lme(fm2) > > sessionInfo() > R version 4.6.1 (2026-06-24 ucrt) > Platform: x86_64-w64-mingw32/x64 > Running under: Windows 10 x64 (build 19045) > > Matrix products: default > LAPACK version 3.12.1 > > locale: > [1] LC_COLLATE=Chinese (Simplified)_China.utf8 > [2] LC_CTYPE=Chinese (Simplified)_China.utf8 > [3] LC_MONETARY=Chinese (Simplified)_China.utf8 > [4] LC_NUMERIC=C > [5] LC_TIME=Chinese (Simplified)_China.utf8 > > time zone: Asia/Shanghai > tzcode source: internal > > attached base packages: > [1] stats graphics grDevices utils datasets methods base > > other attached packages: > [1] car_3.1-5 carData_3.0-6 nlme_3.1-170 piecewiseSEM_2.3.1 > > loaded via a namespace (and not attached): > [1] Matrix_1.7-5 jsonlite_2.0.0 compiler_4.6.1 Rcpp_1.1.2 > [5] DiagrammeR_1.0.12 splines_4.6.1 boot_1.3-32 fastmap_1.2.0 > [9] lattice_0.22-9 TH.data_1.1-5 Formula_1.2-5 MuMIn_1.48.19 > [13] rbibutils_2.4.1 htmlwidgets_1.6.4 MASS_7.3-66 visNetwork_2.1.4 > [17] nloptr_2.2.1 insight_1.5.2 minqa_1.2.8 RColorBrewer_1.1-3 > [21] rlang_1.3.0 multcomp_1.4-31 performance_0.17.1 > estimability_2.0.0 > [25] cli_3.6.6 magrittr_2.0.5 Rdpack_2.6.6 emmeans_2.0.4 > [29] digest_0.6.39 grid_4.6.1 mvtnorm_1.4-2 sandwich_3.1-2 > [33] lme4_2.0-6 reformulas_0.4.4 glue_1.8.1 codetools_0.2-20 > [37] zoo_1.8-15 survival_3.8-9 abind_1.4-8 stats4_4.6.1 > [41] tools_4.6.1 htmltools_0.5.9 > > packageVersion("car") > [1] ‘3.1.5’ > > packageVersion("piecewiseSEM") > [1] ‘2.3.1’ > > packageVersion("nlme") > [1] ‘3.1.170’ > > All the packages are installed from CRAN, and updated to the latest version. > I also run the codes on FreeBSD 15.1, the same output. > > Best, > > Jinsong > >> On 7/19/2026 2:02 PM, varin sacha wrote: >> Hi, >> >> Could this be a package compatibility bug? >> >> Since Anova(fm2), car::Anova(fm2), and even car:::Anova.lme(fm2) all produce >> the same error, it doesn’t appear to be a simple namespace masking issue. >> >> Could you post the output of: >> >> traceback() >> sessionInfo() >> packageVersion("car") >> packageVersion("piecewiseSEM") >> packageVersion("nlme") >> >> That should help identify the exact call that’s failing and whether the >> problem lies in car, piecewiseSEM, or an incompatibility between the two >> packages. >> >> >> >>>> Le 19 juil. 2026 à 04:58, Jinsong Zhao <[email protected]> a écrit : >>> >>> I have tried each solution in a new R session, and neither works. >>> >>>> library(piecewiseSEM) >>> Registered S3 method overwritten by 'lme4': >>> method from >>> na.action.merMod car >>> >>> This is piecewiseSEM version 2.3.0.2. >>> >>> >>> Questions or bugs can be addressed to <[email protected]>. >>>> library(nlme) >>>> library(car) >>> Loading required package: carData >>>> fm2 <- lme(distance ~ age + Sex, data = Orthodont, random = ~ 1) >>>> Anova(fm2) >>> Error in if (random) { : the condition has length > 1 >>>> car::Anova(fm2) >>> Error in if (random) { : the condition has length > 1 >>>> car:::Anova.lme(fm2) >>> Error in if (random) { : the condition has length > 1 > ______________________________________________ [email protected] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide https://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
