When a variety is lost or omitted from a balanced incomplete block design, the residual design is not, in general, balanced. A lower bound is obtained for the overall efficiency in this case and it is shown that the overall loss of efficiency even in the unbalanced case is small.
@article{1176343593,
author = {John, Peter W. M.},
title = {Robustness of Balanced Incomplete Block Designs},
journal = {Ann. Statist.},
volume = {4},
number = {1},
year = {1976},
pages = { 960-962},
language = {en},
url = {http://dml.mathdoc.fr/item/1176343593}
}
John, Peter W. M. Robustness of Balanced Incomplete Block Designs. Ann. Statist., Tome 4 (1976) no. 1, pp. 960-962. http://gdmltest.u-ga.fr/item/1176343593/