This article compares the labor force concepts and methods used in the Survey of Income and Program Participation (SIPP) with those in the Current Population Survey (CPS). The basic labor force estimates from both surveys are then discussed. Of the many possible reasons for the differences in 1abor force estimates, two are examined in detail: coverage and reference period differences. A concluding section discusses the future research required to understand more fully SIPP and CPS labor force differences.

This article which was published in the September 1985 Monthly Labor Review is being made available in the SIPP Working Paper Series in order to broadly disseminate the early findings of this comparison between these two important surveys.