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Pressing plant misspellings in CD matrix fields

One thing that I learned about data entry: it is difficult! People are sloppy and tend to make silly mistakes and then overlook them, because the brain is great at error correction, making you blind for these mistakes.

I bumped into one particular error in Discogs twice while looking at possible errors for specific pressing plants. And, I thought, if I can already see it twice by sampling a small section of releases, then it has to be more common.

The error that I found is that the matrix numbers of the PMDC plants were misspelled as "PDMC" (interestingly, PDMC was another completely unrelated plant).

Some likely reasons:
  • sometimes the matrix is mirrored (tricky for the brain)
  • copy and paste errors from elsewhere
  • (personal) PDMC is easier to say than PMDC
Using my scripts and the latest datadump I found 62 releases with this particular error. They are distributed as follows in Discogs:


Releases where PMDC is likely misspelled as PDMC in the matrix

Inspection of some of these releases showed that in some cases the error had been in there for over a decade.

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