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Level 4 - Cross-Validation & Reality Checks

Level 4 - Cross-Validation & Reality Checks

Section titled “Level 4 - Cross-Validation & Reality Checks”

Goal: Learn to triangulate data across systems (intermediate/advanced).

Never trust one system. Always cross-validate.


This level teaches you to compare data across multiple systems to find truth.

You’ll learn:

  • The 3-system cross-check (ad platform vs attribution vs billing)
  • Why Facebook undercounts (consent gaps)
  • Why 5-20% unattributed sales is normal
  • Daily/weekly reconciliation routines

By the end, you’ll know: “Facebook shows 80, my system shows 100, billing shows 95—so reality is 95, and FB has a 16% consent gap.”


Lessons:

  • Lesson 4.1.1: Why Facebook under-counts, why billing is truth
  • Lesson 4.1.2: Typical pattern: FB 80, your system 100, billing 95
  • Lesson 4.1.3: Exercise - Pull numbers from all 3 systems and compute gaps

Based on: Encyclopedia - Cross-Validation (The Three-System Cross-Check)

Key exercise: For one day or week, get conversion numbers from Facebook Ads, your attribution system, and billing. Compare and explain the gaps.

💡 See Real Example: Moon attribution queries showing sales by traffic source →


Section titled “Module 4.2 - Consent Gaps & Unattributed Sales”

Lessons:

  • Lesson 4.2.1: 5-20% unattributed is normal; >30% is a red flag
  • Lesson 4.2.2: How to compute consent gap and adjust ROAS
  • Lesson 4.2.3: Exercise - Calculate unattributed % for a recent week

Based on: Encyclopedia - Cross-Validation (Facebook Consent Gap, Unattributed Sales)

Key skill: Adjust expectations based on known gaps. Don’t panic when Facebook shows lower numbers.


Module 4.3 - Weekly Reconciliation Routine

Section titled “Module 4.3 - Weekly Reconciliation Routine”

Lessons:

  • Lesson 4.3.1: Checklist for weekly ops
  • Lesson 4.3.2: Exercise - Perform one full reconciliation

Based on: Encyclopedia - Cross-Validation (Reconciliation Best Practices)

Key deliverable: Create your own weekly reconciliation checklist.


The 3 Systems:

  1. Ad Platforms (Facebook, Google): Undercount due to consent (50-80% of actual)
  2. Attribution/Analytics (PostHog, Moon): First-party tracking, most accurate for attribution
  3. Billing (Stripe, payment processor): Ultimate truth for revenue

Facebook Consent Gap:

  • iOS ATT: ~60-70% of iOS users decline tracking
  • GDPR: Many EU users decline cookies
  • Ad blockers: Block Facebook pixel
  • Result: Facebook sees 50-80% of actual conversions
  • Don’t panic and stop profitable campaigns

Unattributed Sales:

  • 5-20%: Normal (direct sales, cookie clearing, device switching)
  • 20-30%: High but manageable
  • 30%: Tracking is broken, investigate

Daily Workflow:

  • Morning: Check FB vs PostHog (campaign decisions)
  • Weekly: Check PostHog vs Billing (validate tracking)
  • Spot-check 5-10 events daily (verify parameters)

After this level, you’ll be able to:

  • Cross-validate data across ad platforms, attribution, and billing
  • Calculate and adjust for consent gaps
  • Identify when unattributed % is normal vs broken
  • Perform weekly reconciliation to catch issues early

You now make decisions based on triangulated data, not single systems.


👉 Continue to Level 5: Level 5 - Advanced Hunting & Diagnosis

Now you revisit earlier topics but go much deeper.