I have this df
df = data.frame(x = 1:3)
converted to a factor
df$x = factor(df$x)
the levels by default are
str(df)
now let's make level 2 as the reference level
df$x = relevel(df$x,ref=2)
everything till now is ok. but when deciding to make the level 1 again as the default level it's not working
df$x = relevel(df$x,ref=2)
str(df)
df$x = relevel(df$x,ref=1)
str(df)
Appreciatethe help.
From ?relevel,
ref: the reference level, typically a string.
I'll key off of "typically". Looking at the code of stats:::relevel.factor, one key part is
if (is.character(ref))
ref <- match(ref, lev)
This means to me that after this expression, ref is now (assumed to be) an integer that corresponds to the index within the levels. In that context, your ref=1 is saying to use the first level by its index (which is already first).
Try using a string.
relevel(df$x,ref=1)
# [1] 1 2 3
# Levels: 2 1 3
relevel(df$x,ref="1")
# [1] 1 2 3
# Levels: 1 2 3