On the recordNovember 13, 1997
when we put together these census blocks for most simple geographical areas, the test that was done on this statistical sampling, or statistical guessing, in 1995 had a plus or minus 35 percent accuracy, plus or minus 35 percent accuracy. That means, if there is a census block and it could be 100 people in it, well, it could be 65, or it could be 135. We do not know. But when we put those census blocks together and they become the building blocks for any representative district, whether it is county board, school board, city council, State representative, State Senate seat, we have to have accurate building blocks to put these together, because I tell my colleagues, when we go to the Federal court, they choose what program they are going to take on what maps are most accurate, which map has the least deviation. In Illinois, in 1991, the Federal Court said that the map that they chose was because 19 out of the 20 districts had a zero deviation, and one district, the southernmost district in Illinois, had plus 2. That takes pretty accurate measurement. That takes pretty accurate block- building, census block by census block.
Source
govinfo.gov




