| Returns to a factor | Returns to scale |
| (i) Short run concept | (i) Long run concept |
| (ii) Only one or some inputs can be changed keeping other inputs fixed. | (ii) All factors are variable |
| (iii) Factor ratio changes. | (iii) No change in factor ratio |
| (iv) There is no change in scale of production. | (iv) change in scale of production |
| (v) Refers to change in output when one input is variable. | (v) Refers to change in output when all inputs are variable. |
