Portfolio Alpha
The excess return that exists only when the allocation decision and the operating execution are both right. Brinson performance attribution splits a portfolio's active return into an allocation effect (did you weight the right bets?) and a selection effect (did each bet perform?); portfolio alpha is the interaction the two lenses miss alone - you have to fund the right edges AND have operated the P&L well enough to capture them.
Why It Exists
An allocator who cannot operate funds the right bets and watches the organization fail to capture them. An operator who cannot allocate executes flawlessly on bets that should never have been funded. Portfolio alpha is the interaction term: it takes knowing which bets to make and having the operating muscle to extract the return. Neither capability prices it alone.
Related Terms
Operational Alpha - Excess return on enterprise value generated through systematic identification and capture of mispriced edges in business operations.
Construction Spread - S = (annual_value x P(success)) / build_cost.
The Conviction Fraction - f* = (mu - r) / (gamma x sigma^2).
Causal Yield - yield = E[Y | do(X=1)] - E[Y | do(X=0)].