尝试进行与多级分析相关的方差分析时,我在 R 中运行代码时遇到问题。我总是收到错误:
$ 未为此 S4 类定义运算符
## Model 0: Model without teams - grand-mean-centered
h2_0_gmc <- lm(PSS_mean ~ PCT_mean_gmc, data = dat_h1_2)
## Model 1: Model with teams - fixed intercept, random slope - grand-mean-centered
h2_1_gmc <- lmer(PSS_mean ~ PCT_mean_gmc + (1 | teamcode), data = dat_h1_2)
## Model 2: Model with teams - random intercept, random slope - grand-mean-centered
h2_2_gmc <- lmer(PSS_mean ~ PCT_mean_gmc + (PCT_mean_gmc | teamcode), data = dat_h1_2)
## Comparison of models
anova(h2_0_gmc, h2_1_gmc, h2_2_gmc)
只需颠倒参数的顺序:
library(lme4)
fm1 <- lmer(Reaction ~ Days + (Days | Subject), sleepstudy)
fm0 <- lm(Reaction ~ Days, sleepstudy)
anova(fm0, fm1)
#Error: $ operator not defined for this S4 class
anova(fm1, fm0)
#refitting model(s) with ML (instead of REML)
#Data: sleepstudy
#Models:
#fm0: Reaction ~ Days
#fm1: Reaction ~ Days + (Days | Subject)
# Df AIC BIC logLik deviance Chisq Chi Df Pr(>Chisq)
#fm0 3 1906.3 1915.9 -950.15 1900.3
#fm1 6 1763.9 1783.1 -875.97 1751.9 148.35 3 < 2.2e-16 ***
#---
#Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
技术说明:
anova
是 S3 泛型。S3 方法调度根据作为第一个参数传递的对象类工作。如果将lm
拟合放在第一位,则调用anova.lm
,它无法处理"merMod"对象。如果将lmer
拟合放在第一位,则调用anova.merMod
,此方法也可以处理"lm"对象。