follow up question of CPSID and SERIAL

Hi Joe,

I just cannot quite understand the meaning of “within-sample and across-sample” in your reply. The “sample” here, does it mean that the very month sample? In every separate month sample, YEAR+MONTH+SERIAL can identify each household but cannot serve as a unique ID when combine several month samples. Am I correct?


Yes, that is correct. Each month in the basic monthly CPS can be thought of as a sample. If you want a unique ID when combining several basic monthly CPS samples, for example when matching the same household in different months, you’ll need to use the CPSID variable.