st: Merge question

[Michael Betz <betz.40@buckeyemail.osu.edu>]

Hi all--I'm having a confusing merge issue. I'm merging on string variables "state" and "county". It works for 99% of the observations, but is having trouble with the counties that begin with "ST". As you can see below, there are what appear to be identical observations that are categorized as "using only" or "master only", though they should be matched. I can't figure out what is stopping them from merging. If I execute count if county=="ST CLAIR", Stata only returns 4, when I would expect 8. Here is my code and part of the resulting merged dataset:

merge 1:1 state county using "stco fips"

county		state	totaloasdi	disabledworkers	fipsstate	
ST CHARLES	MO			29	183	using only (2)
ST CHARLES	LA			22	089	using only (2)
ST CLAIR	IL			17	163	using only (2)
ST CLAIR	MI			26	147	using only (2)
ST CLAIR	MO			29	185	using only (2)
ST CLAIR	AL			01	115	using only (2)
ST CROIX	WI			55	109	using only (2)
ST FRANCIS	AR			05	123	using only (2)
ST FRANCOIS	MO			29	187	using only (2)
ST CHARLES	LA	6317	795			master only (1)
ST CHARLES	MO	35290	3645			master only (1)
ST CLAIR	AL	10905	1810			master only (1)
ST CLAIR	IL	43120	4965			master only (1)
ST CLAIR	MO	2721	410			master only (1)
ST CLAIR	MI	27015	2870			master only (1)
ST CROIX	VI	6879	670			master only (1)
ST FRANCIS	AR	5146	735			master only (1)
ST FRANCOIS	MO	12406	2040			master only (1)

Thanks,
Mike

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