Under-counting

Under-counting– the propensity for some people counting devices to count fewer people than are actually passing through the counting zone. This is a specific weakness where Beam Counters are used across a wide entrance. However, both thermal and video counters can also be subject to under-counting when traffic density reaches extremely high levels. Consistent under counting can be compensated for by adding a factor to each set of counts e.g. daily footfall + 10%.