People who see the "glass as half empty" may be more willing to contribute to a common goal if they already identify with it, say researchers from the University of Texas at Austin, the University of Chicago, and South Korea's Sungkyunkwan University.

According to the studies, people who already care a lot, or highly identify, with a cause are more likely to support financially that cause if a solicitation is framed by how much is still needed, such as, "We still need $50,000 to reach our goal."

However, if people care very little prior to a solicitation, they are more likely to contribute if they knew how much of the goal had already been met—like, "We've raised $50,000 toward our goal."

Psychologist Marlone Henderson, of the University of Texas at Austin, and co-authors professors Ayelet Fishbach, University of Chicago Booth School of Business; and Minjung Koo, Sungkyunkwan University SKK Graduate School of Business; plan to publish their findings in the Journal of Experimental Psychology: General.

"We believe our findings offer organizations several strategies to increase volunteering and donations," says Henderson. "Our findings also imply that during times when prior contributions or donations by others are particularly salient in the public eye, organizations may take the opportunity to promote philanthropy by approaching those who identify less with the beneficiaries or with the helping group, thereby expanding their circle of potential donors."

Five studies measured contributions to goals centered on idea generation and helping victims of various disasters, such as the earthquake in Haiti, wildfires in Southern California, and riots in Kenya.

Possible contributions to these causes include engaging in social movements, pledging to charity, volunteering for community outreach programs, and generating ideas in team meetings.

For one of the studies, a field experiment was done in cooperation with the South Korean office of Compassion International, a Christian child-sponsored organization, shortly after the 2007-08 Kenyan riots.

The study randomly selected 973 people who received a letter that either read, "... we have successfully raised 5,200,000 won (the Korean monetary unit)" or "... we need another 4,800,000 won."

When the letter highlighted to low identifiers what had already been collected, the contribution amount more than doubled to 5,042.92 won from 1,619.43 won. When the amount still needed was highlighted to high identifiers, donations increased to 3,265.31 won from 1,847.39 won.

"People ask themselves one of two questions when deciding whether to invest in one personal goal versus another," says Henderson. "'Is the goal worth pursuing?'

This may signal to people who didn't already care that it's something worth paying attention to and to get onboard.

Or for people who already care: 'Is this progressing at a pace I find sufficient?' If not, it may be a signal to jump in and get involved, so this effort they care about doesn't sink."