如何使用get_contrast获得边际均值

Question

我想使用psycho包中的get_contrasts()函数来获得组的平均值。

在psycho blog (https://neuropsychology.github.io/psycho.R/2018/05/01/repeated_measure_anovas.html)中，他们展示了如何通过get_contrast获得组之间的差异。但我无法获得组之间的边际均值，因为它们显示(见下图)。

​

​

我三次

# same results betwen them
get_contrasts(fit, "Emotion_Condition")
get_contrasts(fit)

# quite obvious it wont work, but at least I tired
get_contrasts(fit, "Emotion_Condition*Subjective_Valence")

# print results 
print(results$contrasts) # only show two levels of factors
print (results) # remove `contrasts` and  show the same outcome as they do

# Here are the codes that they provide

library(psycho)
library(tidyverse)

df <- psycho::emotion %>% 
  select(Participant_ID, 
         Participant_Sex, 
         Emotion_Condition, 
         Subjective_Valence,
         Recall)

library(lmerTest)
fit <- lmer(Subjective_Valence ~ Emotion_Condition + (1|Participant_ID), data=df)
anova(fit)

results <- get_contrasts(fit, "Emotion_Condition")
print(results$contrasts)

# ERRORs! since I cant find the means (mrginal means between groups). it is not possible to plot. 
# How can I get means from results here?

ggplot(results$means, aes(x=Emotion_Condition, y=Mean, group=1)) +
  geom_line() +
  geom_pointrange(aes(ymin=CI_lower, ymax=CI_higher)) +
  ylab("Subjective Valence") +
  xlab("Emotion Condition") +
  theme_bw()

如果有人能帮助我，我将不胜感激。

Answer 1

使用get_means得到估计的边际均值。