Abstract
Equivalence scales express the change in the cost of attaining a certain welfare level when the household composition varies. They are very useful in deflating the budget of different household types to a needs-corrected basis. Though there are several sources for estimating equivalence scales, we only review the methods based on the data of household's expenditure in this paper. These methods are classified into two groups. The first group includes the methods which incorporate the household composition into the estimation of demand equations. The second group includes straightforward procedures for calculation just like the Paashe index or the Laspeyres index in price indicies. We survey several methods in these two groups.
