econ question

A production function has constant returns to scale with respect to inputs with inputs K and L if for any z > 0: F ( z . K , Z . L) = zF(K, L) For example, for a production function with constant returns to scale, doubling the amount of each input (i.e., setting z = 2) will lead to a doubling of the output from the production function. A production function has increasing returns to scale if for any z > 1: F ( z . K, Z . L) > zF( K, L) and decreasing returns to scale if for any z > 1: F( z . K, z . L)