A visitor arrives at the selected landing page (L1) in session S1. They are assigned to the control group and complete their session.
Later, the same visitor returns in session S2, landing on page L2 (which is NOT part of the selected landing page filter).
Expected Behavior: When you group results by control/exposed groups, you'll notice L2 appears in the data even though it wasn't included in the landing page filter.
Why this happens: The visitor was already bucketed into the control group during S1 when they landed on L1. Once bucketed, they remain in that group for all subsequent sessions, regardless of which landing page they use. Therefore, their S2 session on L2 is still attributed to the control group.
Key Points:
Bucketing happens on first qualifying session (L1)
Group assignment persists across sessions
Subsequent sessions count toward the assigned group even if they don't meet original filter criteria
This is why "unfiltered" landing pages appear when grouping by test groups
Visual Flow Diagram
Timeline: Visitor Journey
═══════════════════════════════════════════════════════════════SESSION 1 (S1)
┌─────────────────────────────────────────────────────────────┐
│ Visitor lands on L1 (Selected Landing Page ✓) │
│ ↓ │
│ Filter Check: L1 is in selected pages → PASS │
│ ↓ │
│ Bucketing: Assigned to CONTROL GROUP │
│ ↓ │
│ Session completes │
└─────────────────────────────────────────────────────────────┘ [Visitor leaves site]
↓SESSION 2 (S2) - Same Visitor Returns
┌─────────────────────────────────────────────────────────────┐
│ Visitor lands on L2 (NOT in Selected Landing Pages ✗) │
│ ↓ │
│ Filter Check: L2 NOT in selected pages │
│ ↓ │
│ BUT: Visitor already bucketed in S1 → Stays in CONTROL │
│ ↓ │
│ Session data recorded under CONTROL GROUP │
└─────────────────────────────────────────────────────────────┘