The case for old and new certifications in PSA

[Dyl]

Here are my thoughts about this type of sampling bias that @pfm has brought up previously.

CGC Changed Their Grading Scale & Label

Also consider that the strongest PSA 9s/10s from the 2 cert era or earlier are likely locked away in collections and will not see the light of day for some time. In comparison, almost every 6 cert or 7 cert card will be seen in auction, listed as a BIN, or “flexed” on social media. This is an example of sampling bias where prospective buyers disproportionately see the less desirable older certs, while the “weaker” newer certs are overshadowed by the “stronger” copies from the same era. It creat…