medpolish(x, eps=0.01, maxiter=10, trace.iter = TRUE) plot(medpolish.obj) print(medpolish.obj)
medpolish fits an additive "two-way" (constant + rows + columns)
model to the values given in x using Tukey's
median polish procedure.eps
or until there have been maxiter iterations.
The sum of absolute residuals is printed at
each iteration of the fitting process, if trace.iter is TRUE.
medpolish returns an object of class medpolish (see below).
There are printing and plotting methods for this
class, which are invoked via by the generics
print and plot.
medpolish with the following named components:
overall
| the fitted constant term. |
row
| the fitted row effects. |
col
| the fitted column effects. |
residuals
| the residuals. |
name
| the name of the dataset. |
line.median; aov which for a mean
instead of median decomposition.
## Deaths from sport parachuting; from ABC of EDA, p.224:
deaths <-
rbind(c(14,15,14),
c( 7, 4, 7),
c( 8, 2,10),
c(15, 9,10),
c( 0, 2, 0))
dimnames(deaths) <- list(c("1-24", "25-74", "75-199", "200++", "NA"),
paste(1973:1975))
deaths
(med.d <- medpolish(deaths))
plot(med.d)
## Check decomposition:
all(deaths == med.d$overall + outer(med.d$row,med.d$col, "+") + med.d$resid)