Population vector

In neuroscience, a population vector is the sum of the preferred directions of a population of neurons, weighted by the respective spike counts.¹

The formula for computing the (normalized) population vector, ${\displaystyle F}$, takes the following form:

${\displaystyle F={\frac {\sum _{j}m_{j}F_{j}}{\sum _{j}m_{j}}}}$

Where ${\displaystyle m_{j}}$ is the activity of cell ${\displaystyle j}$, and ${\displaystyle F_{j}}$ is the preferred input for cell ${\displaystyle j}$.

Note that the vector ${\displaystyle F}$ encodes the input direction, ${\displaystyle F_{j}}$, in terms of the activation of a population of neurons.