为了便于重现，您可以在此处下载数据。它的结构是：
> str(data)
'data.frame': 30 obs. of 4 variables:
$ Count: num -15.26 NaN NaN -7.17 -49.37 ...
$ X1 : Factor w/ 1 level "Mean": 1 1 1 1 1 1 1 1 1 1 ...
$ X2 : Factor w/ 10 levels "DC1","DC10","DC2",..: 1 1 1 3 3 3 4 4 4 5 ...
$ X3 : Factor w/ 3 levels "SAPvsSH","SAPvsTD6",..: 1 2 3 1 2 3 1 2 3 1 ...
我运行这个ggplot图表：
ggplot(data=data, aes(x=X2, …