Let's define the transaction cost of credit consumption as $\gamma(c,i)$ where $c$ is consumption and $i$ is a fraction of credit purchase.
If the transaction technology does not exhibit economies of scale,
it can be expressed with some function $v(\bullet)$ as: $\gamma(c,i)=cv(i)$
It means per unit cost of transating goods is independent of the volume transacted.
But in this equation $c$ is left so I wonder how can we say that "it is independent of the volume transacted".
Can anyone tell me the reason?