replications
Number of Replications of Terms
Returns a vector or a list of the number of replicates for each term in the formula.
 Keywords
 models
Usage
replications(formula, data = NULL, na.action)
Arguments
 formula
 a formula or a terms object or a data frame.
 data
 a data frame used to find the objects in
formula
.  na.action
 function for handling missing values. Defaults to
a
na.action
attribute ofdata
, then a setting of the optionna.action
, orna.fail
if that is not set.
Details
If formula
is a data frame and data
is missing,
formula
is used for data
with the formula ~ .
.
Any character vectors in the formula are coerced to factors.
Value

A vector or list with one entry for each term in the formula giving
the number(s) of replications for each level. If all levels are
balanced (have the same number of replications) the result is a
vector, otherwise it is a list with a component for each terms,
as a vector, matrix or array as required.A test for balance is
!is.list(replications(formula,data))
.
References
Chambers, J. M., Freeny, A and Heiberger, R. M. (1992) Analysis of variance; designed experiments. Chapter 5 of Statistical Models in S eds J. M. Chambers and T. J. Hastie, Wadsworth & Brooks/Cole.
See Also
Examples
library(stats)
## From Venables and Ripley (2002) p.165.
N < c(0,1,0,1,1,1,0,0,0,1,1,0,1,1,0,0,1,0,1,0,1,1,0,0)
P < c(1,1,0,0,0,1,0,1,1,1,0,0,0,1,0,1,1,0,0,1,0,1,1,0)
K < c(1,0,0,1,0,1,1,0,0,1,0,1,0,1,1,0,0,0,1,1,1,0,1,0)
yield < c(49.5,62.8,46.8,57.0,59.8,58.5,55.5,56.0,62.8,55.8,69.5,
55.0, 62.0,48.8,45.5,44.2,52.0,51.5,49.8,48.8,57.2,59.0,53.2,56.0)
npk < data.frame(block = gl(6,4), N = factor(N), P = factor(P),
K = factor(K), yield = yield)
replications(~ .  yield, npk)
Community examples
Looks like there are no examples yet.