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The fear that a UBI would undermine work incentives is among the most important sources of resistance to the idea. In Part 1, I argued, on theoretical grounds, that replacing the existing welfare system with a UBI would tend to increase average work effort. This part will look at several sources of evidence that support the theory, beginning with the famous income maintenance experiments (IMEs) of the 1970s and 1980s.
What we can learn from the IMEs and what we can’t learn
The income maintenance experiments in question followed a method known as randomized field trials. Each of the experiments enrolled from several hundred to several thousand households and divided them into two groups. They assigned one group to an experimental income support policy while a control group continued to be covered by existing welfare programs, including Aid for Families with Dependent Children (AFDC), food stamps, and others. IMEs testing various policies took place in New Jersey, Iowa, North Carolina, Indiana, Colorado, and Washington. They covered both urban and rural areas; both single parent and two-parent households; and various ethnic groups.