Are welfare benefits so high they discourage work?

Do most people stay on welfare for eight or 10 years or more?

Do young women have babies just to qualify for welfare?

Is a tendency to go on welfare passed down from generation to generation?

Two leading figures in the national welfare policy debate addressed such widely held public beliefs about the welfare system last week.

On the Senate floor, Daniel Patrick Moynihan (D-N.Y.), making a pitch for his bill to revise the welfare system, showered the Senate with statistics challenging the notion that welfare benefits are excessively high and have grown rapidly over the past decade or so.

In 1970, said Moynihan, the average person on Aid to Families with Dependent Children (AFDC) -- which has about 3.8 million women and more than 7 million children on the rolls -- received a benefit of $140 a month, measured in 1986 dollars.

Sixteen years later, in 1986, that benefit, in the same constant dollars, had dropped to $122.

By contrast, Moynihan said, another public support system for children who have lost the sup- port of a father -- Social Security survivor insurance -- rose from $222 month per child in 1970 to $339 in 1986, measured in constant dollars.

Noting that most children who receive Social Security survivor benefits are white, while the majority of those who receive AFDC are black or Hispanic, Moynihan told the Senate, "We have created an extraordinary institutional bias against minority children." He added in an interview, "Built into our Social Security system is discrimination between majority white children growing up with one parent and minority black children growing up with one parent."

In an article in Science magazine, Greg J. Duncan of the Institute for Social Research at the University of Michigan, with colleague Martha J. Hill and Saul D. Hoffman of the University of Delaware, summarized some of the findings from various welfare studies and from his pioneering longitudinal studies of income in welfare families.

Contrary to a widespread belief that many people stay on welfare almost forever, Duncan and his coauthors said that of all people on AFDC, about 30 percent receive welfare for one or two years, 40 percent for three to seven years and only 30 percent for eight years or more.

Welfare does have some inhibiting effect on work, reducing work effort for female heads of families 180 hours a year on average, according to one recent study, Duncan and his colleagues wrote.

They said a recent comprehensive study suggests that the "amounts of AFDC payments have no measurable impact on births to unmarried women, and only a modest effect on rates of divorce, separation and female head-of-household status."

One finding addresses the popular notion that welfare dependency is handed down from generation to generation.

Based on a 19-year study of the fortunes of representative families, Duncan and his coauthors reported that in families that had not been dependent on welfare while the child was growing up, 91 percent of the daughters were not on welfare when observed later at the ages of 21 to 23.

Where the parents had been moderately dependent on welfare while the child was growing up, 62 percent were not on welfare when observed at the same ages.

Even where the family had been highly dependent on welfare when the child was young, 64 percent of the daughters were not on welfare when observed at ages 21 to 23.

The House passed its welfare overhaul bill, the Family Welfare Reform Act of 1987, on Dec. 16 after weeks of controversy and lobbying by Democratic leaders. The five-year, $5 billion measure would convert AFDC into a program that places adult participants in education and job training programs while providing benefits to their families.