MASS::boxcox fails if (1) the data is a data frame called 'attr' (2)
user doesn't specify y=TRUE, qr=TRUE in the initial lm() fit.
boxcox.lm() calls update(), which apparently finds the built-in
'attr' object instead of the data frame in the global environment.
Is there anything to be done about this (other than the old "don't
use names for your objects that are the same as built-in R functions") ?
cheers
Ben Bolker
library(MASS)
m1 <- lm(height~age, data=Loblolly)
boxcox(m1)
attr <- Loblolly
m3 <- update(m1, data=attr, y=TRUE, qr=TRUE) ## fine
m2 <- update(m1, data=attr)
boxcox(m2)
> Error in model.frame.default(formula = height ~ age, data = attr,
drop.unused.levels = TRUE) :
'data' must be a data.frame, environment, or list
Error in model.frame.default(formula = height ~ age, data = attr,
drop.unused.levels = TRUE) :
'data' must be a data.frame, environment, or list
> traceback()
12: stop("'data' must be a data.frame, environment, or list")
11: model.frame.default(formula = height ~ age, data = attr,
drop.unused.levels = TRUE)
10: stats::model.frame(formula = height ~ age, data = attr,
drop.unused.levels = TRUE)
9: eval(mf, parent.frame())
8: eval(mf, parent.frame())
7: lm(formula = height ~ age, data = attr, y = TRUE, qr = TRUE)
6: eval(call, parent.frame())
5: eval(call, parent.frame())
4: update.default(object, y = TRUE, qr = TRUE, ...)
3: update(object, y = TRUE, qr = TRUE, ...)
2: boxcox.lm(m2)
1: boxcox(m2)