Low-Income and Low-Skilled Workers Involvement in Nonstandard Employment. Survey of Income and Program Participation (SIPP)


The SIPP is a large-scale survey sponsored by the Census Bureau. For the years 1990 to 1993, fresh national samples were drawn annually. Each fresh annual sample constitutes a panel. Each panel is interviewed 8-10 times; each household is interviewed every fourth month, with successive quarters of the sample interviewed in each month. A 1996 panel with interview data through March 2000 has recently been released, although the longitudinal file is not yet available. Given the resource limitations on this project, we analyzed the 1990, 1991, 1992, and 1993 SIPP panels.

In each wave, the basic questionnaire provides data on the primary jobs held during the previous four months. Questions focus on the two jobs held for the largest number of hours. For these jobs, we know earnings or wage rate, months the job was held, usual hours worked per week, industry, and receipt of health insurance coverage. These variables, together with measures of income and public assistance receipt, are the primary outcome measures for our analysis of the subsequent effects of temporary work. The SIPP supplements the basic survey in each wave with detailed topical modules that provide information including employment and welfare recipiency history. These modules are used to select comparison groups with relatively similar work histories.