Estimating numbers of unsheltered homeless people through plant-capture and postcount survey methods.
OBJECTIVE
We sought to increase the accuracy of New York City's estimates of its unsheltered homeless population.


METHODS
We employed 2 approaches to increasing count accuracy: a plant-capture strategy in which embedded decoys (or "plants") were used to estimate the proportion of visible homeless people missed by enumerators and a postcount survey of service users designed to estimate the proportion of unsheltered homeless people who were not visible.


RESULTS
Plants at 17 sites (29%) reported being missed in the count, because counters either did not visit those sites or did not interview the plants. Of 293 homeless service users who were not in shelters, 31% to 41% were in locations deemed not visible to counters.


CONCLUSIONS
Both plant-capture estimation and postcount surveys are feasible approaches that can increase the accuracy of estimates of unsheltered homeless populations.
Hopper
Kim
K
Nathan Kline Institute for Psychiatric Research, 140 Old Orangeburg Rd, Orangeburg, NY 10962, USA. hopper@nki.rfmh.org
Shinn
Marybeth
M
Laska
Eugene
E
Meisner
Morris
M
Wanderling
Joseph
J
D019352:Censuses; D003625:Data Collection / Q000379:methods*; D035082:Federal Government; D006703:Ill-Housed Persons / Q000706:statistics & numerical data*; D006801:Humans; D007407:Interviews as Topic; D015233:Models, Statistical; D009519:New York City; D011338:Probability Theory; D011638:Public Housing; D014481:United States