graph
    %% ==========================================
    %% NODE DEFINITIONS
    %% ==========================================

    %% (Node Group 1) - Investment (Binet & Field brand-building vs activation split)
    I_TV[TV Investment]
    I_BVOD[BVOD / Online Video Investment]
    I_SOC[Social Display Investment]
    I_PROMO[Retailer Promotion Investment]

    %% (Node Group 2) - Channel Reach
    R_TV[TV Effective Reach]
    R_BVOD[BVOD Effective Reach]
    R_SOC[Social Display Effective Reach]
    R_PROMO[Promotion Effective Reach]

    %% (Node Group 3) - Combined Reach
    CR[Combined Effective Reach]

    %% (Node Group 4) - Brand & Activation Memory Structures
    DA[Distinctive Asset Salience]
    CEP[Category Entry Point Linkage]
    MR[Message Recall - the Long]
    PS[Promotional Salience - the Short]
    HAB[Purchase Habit / Familiarity]

    %% (Node Group 5) - Consumer Preference & Macro Context
    Pref[Product Preference]
    CCI[Consumer Confidence Index - macro]

    %% (Node Group 6) - Availability / Retail
    PA[Physical Availability]

    %% (Node Group 7) - Outcome
    Sale[Sale]

    %% ==========================================
    %% CAUSAL EDGES (LOGIC)
    %% ==========================================

    %% 1. Group 1 connects to respective Group 2 nodes
    I_TV    --> R_TV
    I_BVOD  --> R_BVOD
    I_SOC   --> R_SOC
    I_PROMO --> R_PROMO

    %% 2. All Group 2 nodes connect to Group 3
    R_TV    --> CR
    R_BVOD  --> CR
    R_SOC   --> CR
    R_PROMO --> CR

    %% 3. Group 3 connects to all Group 4 nodes
    CR --> DA
    CR --> CEP
    CR --> MR
    CR --> PS
    CR --> HAB

    %% 4. Group 4 nodes combine into Group 5
    DA  --> Pref
    CEP --> Pref
    MR  --> Pref
    PS  --> Pref
    HAB --> Pref

    %% 5. Group 5 connects to Group 6 - preference AND the macro climate
    %%    jointly gate availability (demand-pull + purchase-readiness climate)
    Pref --> PA
    CCI  --> PA

    %% 6. Group 6 connects to Group 7
    PA --> Sale

    %% ==========================================
    %% LITERATURE GROUNDING (see tutorial_prompt.md for full citations)
    %% ==========================================
    %% DA  -> Romaniuk (2018), Building Distinctive Brand Assets
    %% CEP -> Sharp (2010), How Brands Grow — Category Entry Points
    %% MR, PS -> Binet & Field (2013), The Long and the Short of It —
    %%          differential decay rates for brand (slow) vs activation (fast)
    %% HAB -> Ehrenberg-Bass "Double Jeopardy" law (repeat-purchase familiarity)
    %% PA  -> Sharp (2010) — physical availability, the second growth pillar
    %% CCI -> GfK/NielsenIQ UK Consumer Confidence Index (monthly since 1974);
    %%        exogenous macro node, no parents — real historical series, not
    %%        synthetic. Sits beside Pref rather than gating Sale directly:
    %%        low confidence plausibly depresses both retailer promotional
    %%        support (supply side) and household willingness to seek out a
    %%        discretionary treat purchase (demand side) — both are
    %%        "purchase-readiness environment" effects, which is what PA
    %%        already represents (br_chocolate's analogous pop_presence node
    %%        blends demand-pull from preference with exogenous conditions).
