Methodology
How the dip-buy grid is simulated, and what it does not claim.
Data
Primary bars are regular-session US hours, 9:30–16:00 ET, from our hourly vendor. If that vendor is down, Yahoo Finance is the backup. Those two sources can disagree, so a rerun is not guaranteed to match. Only currently listed US stocks and ETFs can be tested, so delisted names are missing (survivorship bias). Data can be delayed, incomplete, or wrong. Yahoo’s terms for commercial use should be read independently; we treat that path as an emergency fallback, not the primary book.
Fills
A buy signal is taken from bar N’s close. The lot fills at bar N+1’s open. That is the “no look-ahead” rule: you cannot buy the same bar that printed the dip.
Each open lot has its own limit sell at buy price × (1 + gain %). If the hour trades through that limit, the fill is the limit. If the open gaps through the limit, the fill is that open. Whole shares only: share count is floor(lot size / fill price). Leftover cash from rounding is not a fractional share.
Grid rules
The first lot buys at the starting price. A new lot is added only when price is your down-% below the lowest still-open lot. Max open lots is floor(total capital / lot size). Commission defaults to $0; slippage defaults to 5 basis points on fills.
What the numbers mean
Total return is ending cash plus open lots marked at the last close, minus starting capital. That is the account result, including losses (or gains) still sitting in unsold lots.
Realized P&L counts only lots that were sold. It can look flat while the account is down.
Buy-and-hold invests the same total capital in whole shares at the first hour’s open. Both percentages use starting capital as the denominator.
Windows
Default window is the last 12 complete calendar months. You can run the last 3 or 5 years. Longer windows are heavier and may cover a shorter span if hourly history is not available that far.
What you get
One $1 payment is one parameter set on one symbol for one window. A $10 pack is 20 runs. Comparing dip % against gain % takes another run. If a paid run fails because data is missing or the engine errors, you are refunded automatically.
Known limits
- No market impact, partial fills, halts, borrow, or taxes.
- Slippage is a flat bps model, not a live spread.
- A 12-month (or even 5-year) path is still one historical path, not a forecast.
- In a downtrend, lots can sit open and tie up capital. That is the strategy’s main failure mode, and the sample cards show it on purpose.
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