Indifference Curves and iso-product Curves Distinguished.
Though iso-product curves are similar to the indifference curves of the theory of demand, one important difference between them is worth
nothing. While an ain difference curve shows all those combinations of two goods which provide equal satisfaction to a consumer, it does not tell us exactly how much satisfaction is derived by the consumer from those combinations. This is because utility or satisfaction being a mental phenomenon cannot be measured in absolute terms. Thus, there are no physical units in which satisfaction can be measured. That is
why we label indifference curves as I, II, III, etc., showing that higher.indifference curves provide greater level of satisfaction, but we cannot say how much greater. On the other hand we can label iso-product curves in the physical units of the output produced without any difficulty. Production of a good being a physical phenomenon lends itself to absolute measurement in physical units. Moreover, if we an iso-product map showing various iso-product curves, it is possible to say by how much production is greater or less on one [so-product curve than on another. We have drawn an iso-product map in Fig. 19.2 showing equal product curves JP, JP’, IP” and iP”‘, which represent 40 units, 60 units, 80 units, I00 units, of output respectively. Thus, iso-product curve JP’ represents an output 20 units greater than on isoproduct curve IP and iso-product curve !P'” yields output 60 units greater than on [P. It is. therefore. possible not only to label iso-product curves by physical units but also to judge how much greater or less is the size of the output on one iso-product curve than on another. This is an advantage.
Fig. 19.2.An isoquant map is a set of isequants, The output level increases as isoquant goes higher to the right.