A data frame with 288 observations on the following 5 variables.
meth
a factor with levels StNew
,
StSkil
, ExpNew
and ExpSkil
, representing the instrument
by user combinations. See below.
item
a numeric vector, the
person ID, i.e. the 72 patients
y
a numeric vector, the
measurements, i.e. vital capacity.
user
a factor with levels
New
Skil
, for the new user and the skilled user
instrument
a factor with levels Exp
and St
, for
the experimental instrument and the standard one.