Why this matters
Position-based attribution (often called U-shaped) splits credit across the first and last touch, with the remainder shared by the middle touches. It helps you show which channels spark interest and which close deals. As a Marketing Analyst, you will use it to allocate budgets, defend channel spend, and improve funnel performance.
- Real task: Re-allocate 20% of paid budget from weak middle-touch channels to the top two initiators of high-LTV customers.
- Real task: Explain a drop in assisted conversions after pausing prospecting campaigns, even if last-click looks fine.
- Real task: Build a board slide that compares first-click, last-click, and position-based results for the quarter.
Concept explained simply
In most journeys, different channels play different roles: one starts the journey, several nurture, and one closes. Position-based attribution reflects this by giving the first and last touches the most credit, and sharing the rest across the middle touches.
Mental model
Think of a relay race. The first runner explodes out of the blocks (first touch), the team keeps pace (middle touches), and the anchor finishes strong (last touch). The win belongs to the team, but the start and finish matter most.
See common default weights
- Classic U-shaped: 40% to first, 40% to last, 20% split evenly across middle touches.
- Variant: 30% to first, 40% to last, 30% to middle (evenly split).
Practical rule for short journeys:
- 1 touch: 100% to that touch.
- 2 touches: 50% / 50% (first / last).
- 3+ touches: apply your chosen split (e.g., 40-20-40).
How it works (step-by-step)
- Define your lookback window (e.g., 30 days) and what counts as a touch (session, ad click, email open with site visit, etc.).
- Build the journey for each conversion in chronological order by user (or account) within the lookback window.
- Choose weights:
- Single touch: 100% to that touch.
- Exactly two touches: 50% / 50%.
- Three or more touches: First = F%, Middle total = M%, Last = L% (e.g., 40%, 20%, 40%). Middle share = M% / number of middle touches.
- Multiply conversion value by each touch’s weight to get credit per touch.
- Aggregate credits by channel, campaign, or source to compare performance.
Implementation tips
- Consistent channel mapping (e.g., utm fields to channel groups).
- Decide whether to collapse consecutive identical touches (e.g., Direct then Direct). Simpler: keep all touches.
- Handle multiple conversions per user separately (each conversion has its own journey and credit split).
Worked examples
Use the classic 40-20-40 split unless stated otherwise.
Paid Search → Organic → Email → Direct → Conversion
First (Paid Search): $40
Middle (Organic, Email): $10 each
Last (Direct): $40
Paid Social → Direct → Conversion
2-touch rule: 50/50
Paid Social: $40, Direct: $40
Organic → Conversion
Single-touch rule: Organic gets $60
Edge cases and how to handle them
- Long journeys: Middle pool is split across many touches. That’s okay—assisted channels still get some credit.
- Ties in time: If two touches share the exact timestamp, use ingestion order or a deterministic rule (e.g., paid before owned).
- Cross-device: If identity resolution is weak, expect more single-touch journeys; interpret results accordingly.
Who this is for
- Marketing Analysts who need a balanced view across prospecting and conversion channels.
- Growth Marketers validating top-of-funnel investments.
- Analysts preparing exec-ready channel performance stories.
Prerequisites
- Basic understanding of multi-touch attribution and channel grouping.
- Comfort with spreadsheets; SQL familiarity is a plus.
- Clear definition of what counts as a touch and a conversion event.
Learning path
- Learn the U-shaped rules (including 1-touch and 2-touch handling).
- Practice with small journeys in a spreadsheet.
- Implement the logic in SQL or your analytics tool.
- Run sensitivity tests (40-20-40 vs 30-30-40) and compare outcomes.
- Present findings with clear caveats and recommended budget shifts.
Exercises (practice now)
These mirror the Exercises section below so you can practice inline and then check solutions.
Journeys and values:
- Conv A (Value $120): Paid Search → Organic → Email → Direct
- Conv B (Value $80): Organic → Direct
- Conv C (Value $150): Referral → Paid Social → Paid Search → Direct
Hint
For 3+ touches: First=40%, Last=40%, Middle=20% split evenly. For 2 touches: 50/50. Sum credits by channel at the end.
Recalculate credits for the same journeys using:
- 1 touch: 100%
- 2 touches: 50/50
- 3+ touches: First=30%, Middle total=30% (even), Last=40%
Hint
Remember to split the middle 30% evenly across middle touches only.
- Checklist before you move on:
- You can correctly allocate credit for 1-, 2-, and 3+ touch journeys.
- You can aggregate per-channel totals from touch-level credits.
- You can explain how different splits (40-20-40 vs 30-30-40) affect channel winners.
Common mistakes and self-check
- Forgetting special rules for 1- and 2-touch journeys. Self-check: Do 2-touch journeys sum to 100% with 50/50?
- Inconsistent channel mapping. Self-check: Are utm_source/medium mapped the same way across all conversions?
- Dropping middle touches due to filters. Self-check: Count touches per journey before and after filters—they should match.
- Mixing users, sessions, and accounts. Self-check: Is your attribution entity consistent (user or account)?
- Ignoring lookback windows. Self-check: Are touches outside the window excluded consistently?
Quick diagnostic
- Sum of credits across all channels must equal total conversion value.
- Channel totals should change predictably when you switch weight variants.
Practical projects
- Build a spreadsheet model that turns a list of journeys into channel credits using configurable weights.
- Implement position-based logic in SQL and produce a channel leaderboard for last quarter.
- Run a sensitivity analysis comparing 40-20-40 vs 30-30-40 and recommend a budget shift.
- Create a one-page memo explaining why prospecting matters even if last-click looks weak.
Mini challenge
Your company launches a new product with long consideration. Propose a position-based split for the campaign and explain—in 3 sentences—how it changes budget allocation compared to last-click.
Thought starter
Consider 30-40-30 or 30-30-40 depending on how nurturing-heavy the journey is. Expect prospecting and mid-funnel channels to gain credit.
Quick Test and progress
Take the Quick Test below to check your understanding. The test is available to everyone; only logged-in users will have their progress saved.