显示ggplot BOXPROOT的意外结果

我正在绘制这些数据：

Day,Property,Violent
Mon,7.2,5.7
Tue,5,4.5
Wed,6.3,3.6
Thu,5.4,4
Fri,9.5,5.6
Sat,16,10.9
Sun,14.2,8.6

使用以下代码：

library(ggplot2)
library(reshape)
week <- read.csv("week.csv", header=TRUE)
data.melt <- melt(week,id="Day")

ggplot() +
geom_boxplot(aes(x=Day, y= value, fill= variable), 
             data= data.melt, position = position_dodge(width = .9))

库（ggplot2）
图书馆（重塑）
周

DF <- read.table(text="Day,Property,Violent
Mon,7.2,5.7
Tue,5,4.5
Wed,6.3,3.6
Thu,5.4,4
Fri,9.5,5.6
Sat,16,10.9
Sun,14.2,8.6", header=TRUE, sep=",")

#I would consider the weekdays ordered, so let's turn them into an ordered factor.
DF$Day <- ordered(as.character(DF$Day), as.character(DF$Day))

library(ggplot2)
library(reshape2)
data.melt <- melt(DF,id.vars="Day")

ggplot() +
  geom_boxplot(aes(x=Day, y= value, fill= variable), 
               data= data.melt, position = position_dodge(width = .9))

ggplot() +
  geom_point(aes(x=Day, y= value, colour= variable), 
               data= data.melt, position = position_dodge(width = .9))