Symbol I_t

Its job in the formula

$I_t$ is one of the signed contributions combined to compute the quantity on the left.

Where the article explains it

Here $C_t$ is the stock of cultural complexity in circulation at time t ; $\rho_t$ $\in$ [0,1] is the transmission-fidelity coefficient — the share of $C_t$ that survives one round of copying, the same quantity Henrich’s Tasmania case shows collapsing when the effective transmitting population shrinks; $I_t$ is genuinely new human innovation entering the pool; and $L_t$ is loss from forgetting, obsolescence, or population decline.

Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

Open the illustrated subscripts: which member of a family? guide →