Where aij is the weight attached by individual j to a unit of the utility of individual i. Sen is interested in comparing two main methods of income distribution: “to each according to his needs” and “to each according to his work”. It is therefore assumed that a proportion of income is distributed according to need (with needs being equal), and the rest (1 ) according to work. Denoting by Y the total income generated in the LMF, by N the number of workers and by L total supply of labour, we have the following definition of income for workers: