Singapore - Begging is illegal here, under the island-nation's Destitute Persons Act, carrying a fine of up to $3,000 or imprisonment for up to two years for repeat offenders.

But Singapore's poor still can be found, often selling packets of tissues outside food centres. Or spending the night on benches near their jobs to save the transport fare home - they are commonly called "sleepers". Or collecting empty soft drink cans out of trash bins.

The poor have no place in Singapore's vaunted success story, but there are growing calls for one of the wealthiest countries in the world to acknowledge rapidly rising income inequality by setting an official poverty line. Hong Kong's recent decision to set a poverty line as a way to better identify and assist its poor has prompted a similar debate in Singapore's parliament.

A report to be formally released on November 11 says Singaporeans are not aware of the scale and depth of poverty. Meanwhile, a new public awareness campaign challenges citizens to try living on $5 for a day in a nation with one of the highest costs of living in the world.

But even as government spending on anti-poverty efforts is rising - assistance payments to the poor exceeded $100m Singaporean dollars for the first time last year, a nearly 45 percent jump from the previous year - business-minded Singaporeans are balking at the idea.

Some 105,000 households in Singapore - that's one in 10 family homes, or 387,000 people - earn an average monthly income of $1,323 and some 114,000 individual residents earn less than $805 a month, according to government data. That's despite the country's average per capita income of $52,305 a year, one of the highest in the world.

While Singapore has no official measure of poverty, the average household spends $1,250 a month for a four-person household on basic needs - food, clothing and shelter, says a two-year-old survey held by the Department of Statistics.

"In light of rising concerns about increasing inequality, and debate about the existence, extent and nature of poverty in Singapore, it is time for Singapore to join comparable developed nations in officially defining and measuring poverty," reads the report to be released Monday by Singapore Management University's Lien Centre for Social Innovation.

In the report, a team of researchers and policy experts say officially defining and measuring poverty will help to identify at-risk households and to measure the performance of efforts to lift people out of poverty.

The report cites two measures of inequality in Singapore. First, the period from 1998 to 2010 saw the real median income of employed residents in the bottom 20 percent fall by approximately 8 percent, while the income of those in the highest-earning quintile increased by 27 percent. Second, Singapore's Gini coefficient - which measures the degree of inequality within the country - increased between 2002 and 2012 at a rate that far outpaces the rest of the developed world.

"Rising inequality does not necessarily denote the existence of poverty. However, rising inequality combined with evidence of poverty indicates that the poor are being left further behind, and this appears to be what is happening in Singapore," reads the report.

Income inequality



Singapore does not have as high percentages of impoverished residents as those in the less developed world, and its poor tend to go unnoticed amid the country's steel-and-glass opulence. But researchers point to a growing inequality - it ranks 26th out of 136 countries for income inequality - and a high cost of living: In 2012, Singapore was the world's sixth most expensive country to live in, according to the Worldwide Cost of Living Survey 2013.

Yet Singapore's poor are largely hidden, in part because affordable public housing typically means a roof over the heads of the working poor and elderly poor. That helps to create an overall impression that poverty and homelessness may exist only negligibly, if at all.

Reflecting that view, a leading academic, Kishore Mahbubani, dean of the Lee Kuan Yew School of Public Policy, wrote in 2001: "There are no homeless, destitute or starving people in Singapore. Poverty has been eradicated, not through an entitlements program (there are virtually none) but through a unique partnership between the government, corporate citizens, self-help groups and voluntary initiatives."

The fact that many needy residents live in the shadows of a rich society prompted a new campaign to raise awareness about the poor in Singapore. Singaporeans Against Poverty, launched in October and organised by Caritas Singapore, a Catholic social action group, is intended to operate for three to five years.

"This is not a charity or donation drive. We want to set everyone thinking about the poor in Singapore. Who are they? Why are they in such a plight? How do they survive?" said Caritas Singapore advocacy committee chairman and member of parliament Laurence Lien. "We want to start a conversation. We invite everyone to move out of their comfort zones to join in this conversation."

Public service advertisements include videos showing everyday citizens making decisions about what to eat, what to wear, and how to spend money, with the tagline: "105,000 low-income families would gladly swap their problems with yours." There is a webpage with facts about income inequality and a planned online educational game.

The campaign also urges the public to participate in its $5 challenge, which is based on the statistic that some 387,000 Singaporeans only have about $5 a day to spend on food and transport per family member. Radio personalities have been enlisted to join the campaign and make on-air appeals for listeners to do the same.

The 'cliff effect'



Calls for Singapore to follow Hong Kong's lead prompted a debate in parliament in late October, where Chan Chun Sing, Minister for Social and Family Development, expressed the government's opposition to the idea. He said he worries a single measure would allow some needy people to fall through the cracks.

"In Singapore, we use broad definitions for the groups we seek to help, have clear criteria to identify and assess those in need, and tailored schemes to assist them," he said in a written reply. "A poverty line does not fully reflect the severity and complexity of the issues faced by poor families, which could include ill health, lack of housing or weak family relationships."

Chan added: "If we use a single poverty line to assess the family, we also risk a 'cliff effect', where those below the poverty line receive all forms of assistance, while other genuinely needy citizens outside the poverty line are excluded. Our assessment process is rigorous but also flexible to cater to the genuinely needy. Singaporeans who do not meet scheme criteria but who still deserve help, can receive assistance."

Singaporean bloggers were quick to criticise Chan's comments. "Chan's answer reinforces a general view about this government. They really do not want to provide social assistance," wrote Alex Au Waipang on his popular blog Yawning Bread.

"At heart they really do believe in trickle-down and little else. They only get into social assistance when they can't avoid it and a problem is staring them in the face."

Follow Tom Benner on Twitter: @tgbenner