The variable migmet1 in ACS has lots of value 0 or N/A. Does it mean that the individual stay in the same metropolitan area one year ago, or the infomation is not available?
The code MIGMET1==0 “N/A” identifies people who were outside of the question universe. For the 2005-onward ACS samples respondents were coded as MIGMET1==0 if they were under the age of 1, were living in the same house as they were the previous year (didn’t move), or they moved but were not living in an identifiable U.S. metro area. You can use the variable MIGRATE1 to identify which of these reasons a respondent was given a code of MIGMET1==0. If MIGRATE1==1 the respondent did not move, if MIGRATE1==2 or 3 the respondent did move within the U.S. but they did not previously live in an identifiable metro area, and if MIGRATE1==4 the respondent lived outside of the U.S. the previous year.
I hope this helps.
I would like to confirm whether really all respondents with migmet1 == N/A either lived in the same house 1 year ago or moved from outside an identifiable metropolitan area? I am asking because there is a very large number of respondents who have migmet1 == N/A but migrate1 either “Moved within State: Moved within MIGPUMA” or “Moved within State: Moved between MIGPUMAs”. Have all of these respondents moved from outside an identifiable metropolitan area? Metropolitan areas seem to only rarely cut across PUMAs…
Just to clarify my own follow-up question above: I am referring to respondents who currently live in an identifiable METAREA and who have MIGMET1 == N/A. I would like to make sure that those with MIGRATE1 != “Same house” have indeed moved from outside the current METAREA and not just within a PUMA or between PUMAs that are part of the current METAREA.
Notice that MIGPUMAs and PUMAs do not necessarily share boundaries. MIGPUMAs are generally aggregations of PUMAs, so there are far fewer identifiable MIGMET1 metropolitan areas then are identified in METAREA. This is why there are so many MIGMET1==N/A respondents with a MIGRATE1 code of 2 or 3.