A new data mining approach to estimate causal effects of policy interventions

A multivariate strategy to measure and test global imbalance in observational studies

“…The B matrix, which represents the structure induced by T on data, has row margins b t: Camillo and D'Attoma (2010) and D'Attoma (2009), a default analysis that deals with the factorial decomposition of the inertia related to the juxtaposition of the K and T table, in the presence of categorical variables, is Multiple Correspondences Analysis (MCA) (Benzécri, 1973;Greenacre, 1984;Greenacre & Blasius, 2006;Jobson, 1992;Lebart, Morineau, & Tabard, 1977;Saporta, 1990) that aims at studying the marginal links between pairs of categorical variables in a given table and studying the structure induced by these variables on the units (Estadella et al, 2005). MCA (Benzécri, 1973) is a popular explorative multivariate technique for the analysis of any kind of matrix with nonnegative entries, but it especially involves table of frequency or counts with more than two dimensions in which makes sense the sum by rows or by columns.…”

“…As reported in Camillo and D'Attoma (2010) and D'Attoma (2009) the starting information is represented by the X matrix and the assignment-to-treatment indicator vector T. In particular, they assume to have enough information in the observable pretreatment covariates so that the X matrix generally includes all pre-treatment variables associated with both the assignmentto-treatment T and the outcome Y.…”

“…To do that, we analyze the association among variables within the framework of multivariate descriptive analysis introduced in Camillo and D'Attoma (2010) and D'Attoma (2009).…”

“…Specifically, the conditioning was applied to the problem of measuring imbalance with categorical covariates (X) where all or some of them may be linked to an external categorical variable (T) (Camillo & D'Attoma, 2010;D'Attoma, 2009). Authors adopted the concept of inertia as a measure of association among categorical covariates, where the term inertia is used by analogy with the definition in applied mathematics of moment of inertia which stands for the integral of mass times the squared distance to the centroid (Greenacre, 1984).…”

“…Our strategy, mainly based on the multivariate approach introduced in Camillo and D'Attoma (2010), D'Attoma (2009), involves two steps.…”