From PURCHASE to FALLING: How Alpha Engine's Six Signals Work

We think a price tool should never ask you to “just trust the algorithm.” So here is precisely how every card gets its label — no black box.

The inputs

Each card is scored on two things from its real price history: a 3-day Rate of Change (how fast it's moving) and a 3-day vs. 14-day moving-average relationship (whether recent strength has overtaken the baseline).

Confirmed across two markets

A single market can lie to you — one odd sale spikes a chart. So a PURCHASE isn't called on our US TCGplayer read alone: it has to line up with an independent Cardmarket (EU) uptrend and a liquid price spread. When the two markets disagree, or the low-to-high spread is wide enough that the price is thin, the call is capped at ACCUMULATE — real momentum, but scale in rather than full-send. That's the honest difference between “buy” and “accumulate.”

The six calls

• PURCHASE — strong momentum (ROC over ~15%) and a confirmed moving-average crossover. Both boxes ticked.
• ACCUMULATE — real momentum (over 5%) with the short-term average above the baseline: trend support without a confirmed crossover yet. The early-entry zone.
• WATCHING — upward momentum without trend support. Worth eyes, not money.
• FALLING — downside momentum worse than -10%. A live slide is not a dip; wait for it to stabilize.
• STAGNANT — enough data to know momentum is flat; nothing actionable right now.
• GATHERING — not enough price history to judge. We say so instead of pretending.

Why we show our work

Open any card and you'll see the exact ROC, both moving averages, the spread between them, and a plain-English justification. Signals are analytical estimates from past prices — not guarantees, and not financial advice. The point is to do the heavy lifting across 20,000+ cards so you can make a faster, better-informed call yourself.