EaseOfMovement — Ease of Movement

How far price moved per unit of volume: high when a small amount of trading moved the market a long way, near zero when heavy volume produced nothing. Arms’ original point was that the effort behind a move matters as much as the move.

Signature

EaseOfMovement(period, scale, on=<source>)

Argument	Type	Required	Notes
period	int Param or literal	Yes	Smoothing window. Default 14, bounds 1–400.
scale	int Param or literal	Yes	Volume divisor keeping the value readable. Default 1,000,000. Bounds 1–1e9.
on=	symbol	No	Source symbol. Defaults to the trade symbol. Reads high, low, volume.

Formula

$$ \text{EMV} = \frac{\text{midpoint move}}{(V/\text{scale}) / (H-L)}, \quad \text{then averaged over } n $$

Warmup

period + 1 bars; zero-volume or zero-range bars contribute 0.

Reading the value

emv.value
emv > 0

Example

class EaseEntry(Strategy):
    """Enter when price is moving easily upward."""
    trade = Symbol()
    sizing = FixedCapital()

    def execute(self):
        emv = EaseOfMovement(14, 1000000, on=self.trade)
        if emv.value > 0 and self.trade.is_flat:
            self.buy(self.trade, reason="Rising with little effort")
        if emv.value < 0 and self.trade.is_long:
            self.sell(self.trade, self.trade.position, reason="Effort against us")

Notes

• Richard Arms’ Ease of Movement Value.
• The scale parameter exists because raw volume makes the box ratio unreadably small; it is presentational and does not change the sign.
• Ours reads 0.01× pandas_ta’s eom(14) on the same bars — the reference applies a ×100 scale factor this implementation does not; the shape is identical.