Table 1.

Achieved level of significance (ALS) of maximum differences in R_eff associated with a partition of housing blocks according to various socio-economic indicators. ALSs have been obtained by comparing these differences in R_eff with those obtained from 99 bootstrapping random partitions.

Socio-economic indicator	ALS
Living space per person	1 per cent
Median income	2 per cent
Fraction of 1-person households	2 per cent
Fraction of residents aged above 64	45 per cent