[R] test for connectedness

[Joerg Schaber]

Hi,

in a 2-way linear model with missing data the normal equations can 
sometimes be separated in 2 or more independent sets of equations 
brought about by the nature of the missing data. As far as I know this 
phenomenon is called  'connectedness' of the data.
Does anyone know of a test or algorithm in R that extracts the connected 
sets from the data (all I need is an algorithm for a 2-way classification)

greetings,

joerg