我用r做lmm模型,对1个具有3个水平的固定因子的原始数据进行了宽转长的操作。但是我的结果默认将其中一个水平的固定因子作为分类变量处理了,该怎么办?
data2 <- speed%>%pivot_longer(4:6,names_to='strategy', values_to='Speed')%>% filter(Speed>0)
dummies <- model.matrix(~ as.numeric(data2$strategy == "Conventionally.indirect.strategy.speech.rate") - 1, data = data2)
dummies <- model.matrix(~ as.numeric(data2$strategy == "Direct.strategy.speech.rate") - 1, data = data2)
dummies <- model.matrix(~ as.numeric(data2$strategy == "Non.Conventionally.indirect.strategy.speech.rate") - 1, data = data2)
data3 <- cbind(data2, dummies)
model <- lmer(Speed ~ strategy +
Chinese.proficiency.levels +
strategy:Chinese.proficiency.levels +
(1 | Speakers), data = data3)
在代码中,我尝试设置虚拟变量,好像没啥用,最后还是产出了2个水平。所以……求解答。