★ What's in the feed
Three layers, all updated daily
Daily change in PSA Pop Report counts at the (set × card × grade) level. Spot scarcity collapse before the market does.
Aggregate accuracy data: for every (set × card), what did we predict vs. what came back? Calibration metric for the market.
For each card, the PSA-vs-BGS-vs-SGC realized price spread. Where arbitrage lives.