---
name: evaluate-channel-mix
description: "Evaluate channels on contribution and marginal ROI under a stated attribution model — not average ROI or lead count. Reach for this on a channel or budget question."
---

# Skill: Evaluate channel mix

Attribution choice changes the ranking, and average ROI hides saturation (§3 #2 #5).

## Step 1 — State the attribution model
First/last/multi-touch named before any number (§3 #2).

## Step 2 — Compute channel ROI
(Contribution − cost) ÷ cost via `marketingops_calc.py channel-roi`.

## Step 3 — Read marginal ROI
The next dollar's return, not the blended average (§3 #5).

## Step 4 — Reallocate
Move budget off saturated channels toward higher marginal ROI.

## Output
A channel read with the attribution model named and marginal-ROI reallocation.