Forward return

For each EMA cross up, measures the return from the cross close to the close a set number of minutes later, then publishes the spread of those returns.

What it measures

Forward return in basis points after ema_cross_up, over a horizon the trader sets before each run.

Key decisions

Piece	Why
`params.horizonMin`	The trader changes the horizon in the run dialog without editing code.
`scope` returns `{}`	The event joins the sample from what is known when it fires, even when the horizon bar is not loaded yet.
`ctx.candles.forward({ minutes })`	Returns the one bar at or just before event time plus the horizon, or nothing past the end of the data.
Entry from `payload.close`	The close the definition emitted at the cross.
`ctx.priceUnits.inBP`	Basis points compare across instruments and price levels.
`kind: "distribution"`	Takes a plain array of numbers.

Full script

meta({
  name: "EMA cross forward return",
  kind: "study",
  params: {
    horizonMin: { type: "number", def: 60, min: 1, max: 1440, step: 1 },
  },
});

flows.declare({ slug: "ema-cross-up", as: "xup", version: 2 });

results.declare({
  id: "readout__summary",
  kind: "prose",
  role: "answer",
  title: "Summary",
  description: "The typical move after an EMA cross up, in plain words.",
});

results.declare({
  id: "readout__events",
  kind: "metric",
  title: "Crosses measured",
  description: "EMA crosses up with a bar at the horizon.",
});

results.declare({
  id: "readout__median_bp",
  kind: "metric",
  title: "Median return (bp)",
  description: "Median close-to-close return over the horizon, in basis points.",
});

results.declare({
  id: "fwd_ret",
  kind: "distribution",
  size: "lg",
  title: "Forward returns (bp)",
  description: "Close-to-close return from the cross to the horizon bar, in basis points.",
});

export function scope(ctx) {
  if (ctx.event.flow !== "xup") return null;
  return {};
}

export function onEvent(ctx, scope) {
  const entry = Number(ctx.event.payload.close);
  if (!Number.isFinite(entry) || entry === 0) return;
  ctx.mark(ctx.event.time, entry, { color: "#26a69a", shape: "circle" });

  const after = ctx.candles.forward({ minutes: ctx.params.horizonMin });
  if (!after) return;

  ctx.collect("rets", ctx.priceUnits.inBP(after.close, entry));
}

export function onFinish(ctx) {
  const rets = ctx.collected("rets");
  const median = rets.length ? ctx.stat.median(rets) : 0;

  ctx.publish("readout__events", { value: rets.length, format: "integer" });
  ctx.publish("readout__median_bp", { value: median, n: rets.length });
  ctx.publish("fwd_ret", rets);
  ctx.publish("readout__summary", {
    body: rets.length
      ? `${rets.length} crosses. Median return after ${ctx.params.horizonMin} minutes: ${median.toFixed(1)} bp.`
      : "No crosses had a bar at the horizon.",
    role: "answer",
  });
}

Because it reads forward, this study can be attached to the chart. With no dimensions it pins as one global card. To get a reading per session or trend state, add a scope dimension as in Stop / target first hit.

PreviousEvent count NextStop / target first hit