skewness(x, ...)# S3 method for default
skewness(x, na.rm = FALSE, method = c("moment", "fisher"), ...)
# S3 method for data.frame
skewness(x, na.rm = FALSE, method = c("moment", "fisher"), ...)
# S3 method for POSIXct
skewness(x, ...)
# S3 method for POSIXlt
skewness(x, ...)