In estimating the relationship between the reward for working and work efforts, the authors use cross section studies, social experiments, and studies of related transfer programs, such as Aid to Families with Dependent Children and Old Age Insurance. From the available empirical evidence, they conclude that the Unemployment Insurance system does have some work disincentive effects, but they say that these studies do not enable them to ascertain the magnitude of the overall effects. The short-term work disincentive effects, that is, reductions in worktime attributable to the Unemployment Insurance system, the authors say, may lead to increased job stability, higher labor productivity, and lower rates of unemployment over the longer run because of the "suitable employment" provisions of the program. That is, the unemployed worker who turns down an unsuitable job may search further and obtain a more suitable job which will enable him to be a more productive member of society. The creation of work disincentives is an unavoidable cost of the program, the major objective of which is to provide adequate income replacement; the more generous the benefit provisions, the more adequately the system fulfills its goal, and the greater, also will be the work disincentive effects. (Author/AJ)