使用 geom = "errorbars" 的错误栏位置错误答案

【问题标题】：Wrong position of errorbars using geom = "errorbars"使用 geom = "errorbars" 的错误栏位置错误
【发布时间】：2018-12-01 18:25:00
【问题描述】：

我正在尝试将错误栏添加到我创建的图表中：

如您所见，错误栏不在正确的位置，我不知道为什么。以下是我使用的代码：

df_midtermclean$gender <- factor(df_midtermclean$ï..gender, labels = c('Male', 'Female'))  

#reshaping from wide to long format

data_long <- melt(df_midtermclean,
                  # ID variables - all the variables to keep but not split apart on
                  id.vars=c("gender"),
                  # The source columns
                  measure.vars=c("sSkills", "sPerform", "sComplex", "sIQ" ),
                  # Name of the destination column that will identify the original
                  # column that the measurement came from
                  variable.name="measures",
                  value.name="score")        

p2 <- ggplot(data_long, aes(measures, score)) + stat_summary(fun.y = mean, geom = "bar", aes(fill = gender), position = "dodge") 
    p2 <- p2 + stat_summary(geom = "errorbar", fun.data = mean_cl_normal, position = position_dodge(.9), width = .1)
    p2 <- p2 + labs(x = "Continuous Measures", y = "Participant Scores", fill = "Gender")
    p2

数据。

data_long <-
structure(list(gender = structure(c(1L, 1L, 1L, 
1L, 1L, 1L, 2L,  1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 
2L, 2L, 1L, 1L, 1L), .Label = c("Male",  "Female"), 
class = "factor"), measures = structure(c(1L, 1L,  
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L,  1L, 1L), .Label = c("sSkills", 
"sPerform", "sComplex", "sIQ"), class = "factor"), 
score = c(4.75, 3, 3.5, 3.75, 3, 3.25, 3.25, 3, 
2.75, 2.75, 2.5, 2.75, 3.75, 3.5, 3.75, 3.75, 
3.25, 3.25, 4, 3.25)), row.names = c(NA,  20L), 
class = "data.frame")

【问题讨论】：

您可以发布示例数据吗？请使用dput(data_long) 的输出编辑问题。或者，如果 dput(head(data_long, 20)) 的输出太大。
我已经添加了:)

标签： r

【解决方案1】：

不幸的是，您的代码无法重现！不过，我可能会在 http://www.sthda.com/english/wiki/ggplot2-error-bars-quick-start-guide-r-software-and-data-visualization 上找到解决方案

library(ggplot2)

df <- ToothGrowth
df$dose <- as.factor(df$dose)

# Function to calculate the mean and the standard deviation
data_summary <- function(data, varname, groupnames){
  require(plyr)
  summary_func <- function(x, col){
    c(mean = mean(x[[col]], na.rm=TRUE),
      sd = sd(x[[col]], na.rm=TRUE))
  }


 data_sum <- ddply(data, groupnames, .fun=summary_func, varname)
 data_sum <- rename(data_sum, c("mean" = varname))
 return(data_sum)
}

# New dataframe
df2 <- data_summary(ToothGrowth, varname="len", 
                    groupnames=c("supp", "dose"))

df2$dose <- as.factor(df2$dose)

ggplot(df2, aes(x=dose, y=len, fill=supp)) + 
  geom_bar(stat="identity", color="black", position=position_dodge()) +
  geom_errorbar(aes(ymin=len-sd, ymax=len+sd), width=.2, position=position_dodge(.9))

【讨论】：

【解决方案2】：

我认为你的代码的第二行应该是以下格式：

 geom_errorbar(aes(ymin = lower, ymax = upper), position = dodge, width = 0.25)

我不确定您的代码中的 stat_summary 是什么，您能解释一下吗？但是，您需要明确提及误差线的下限和上限，我认为您的代码中没有包含。

编辑：尝试调整 position=position=position_dodge(0.9) 以及大小和宽度。

【讨论】：

geom_errorbar() 根据这个似乎没有必要：stackoverflow.com/questions/44872951/…
尝试调整 position=position=position_dodge(0.9) 以及大小和宽度。

【解决方案3】：

我相信像下面这样的东西会做你想要的。

agg <- aggregate(score ~ gender + measures, data_long, function(x) c(mu = mean(x), se = sd(x)))
agg <- cbind(agg[-ncol(agg)], agg[[ncol(agg)]])

p2 <- ggplot(agg, aes(measures, mu, fill = gender, group = gender)) +
  geom_bar(stat = "identity", position = "dodge") +
  geom_errorbar(aes(ymin = mu - se, ymax = mu + se),
                position = position_dodge(0.9),
                width = 0.1)

p2

【讨论】：