Harlem — Before their potential new neighbors ever arrived, some tenants at the Astoria Houses, a public housing complex in Queens, hardly planned to roll out the welcome wagon. The 50 mentally disabled homeless people who could move in across the street were inspiring dismay, not acceptance.

One Astoria Houses resident of three decades, Dolores Battey, 50, herself works with mentally disabled people at a major human services agency, where she is a short-term case manager. She said the mentally disabled “will eventually wander off course” and threaten residents at her complex.

Former longtime tenant Sandra Grady, 47, who was visiting her sister at the Houses, said she was concerned about the broader community. She pointed out that the supportive housing development might sap the equity of the new condos next to it. “That’s not fair, I think it’s going to bring their values down,” Grady said.

City Councilman Peter Vallone Jr., who represents Astoria, also vehemently opposed the proposal, which was rejected in December by a 35-1 vote of Community Board 1. “There’s no reason for myself or anyone else to be subjected to 50 mentally ill homeless people,” Vallone said.

Developers of supportive housing – subsidized, service-rich residences for a variety of people at risk for homelessness, from youths aging out of foster care, to people living with HIV/AIDS, to substance abusers or ex-offenders – are used to an automatic "not in my back yard" reaction. Residents' objections are often a given at community board meetings around the city when nonprofit organizations propose new supportive housing developments. In light of the Bloomberg administration's expressed commitment to keep building these projects, however, the trend toward supportive housing expansion continues – and now a study has been published that claims the usual objections are unfounded.

“I think a lot of opposition to supportive housing is based on abstract stereotypes that don’t turn out to be true,” said Vicki Been, the director of the Furman Center for Real Estate and Urban Policy at NYU and an author of the recent paper, "The Impact of Supportive Housing on Surrounding Neighborhoods: Evidence from New York City."

The study found that property values actually increase near supportive housing developments. This challenges one typical line of NIMBY opposition – worries about sinking property values – and raises questions about what role community members should have in the supportive housing review process.

Been's researchers looked at 123 developments built in New York City and measured the price changes of surrounding housing before and after the residences were completed. To control for varying market conditions, the researchers studied projects built between 1985 and 2003. They found that after a development opened, on average, the buildings within 500 feet of supportive housing appreciated at a faster rate than the buildings in the control group located 1,000 feet away (but still in the same neighborhood, as defined by census tracts). In other words, it looks like supportive housing may positively affect nearby property values.

Been gives two possible explanations. One is that many supportive housing developments are sited on eyesores—either empty vacant lots or in dilapidated buildings. Also, she said, they are exceptionally maintained because government officials and neighbors hold them accountable. “There are a lot of incentives to have the best house on the block,” said Been.