translate English to French: The purpose of this work was to determine whether certain changes in the composition of the population, in terms of socio-economic characteristics such as age, occupation, class of worker, etc., could have masked positive changes in training participation rates among different groups of workers during the 1990s.
La manière de décomposer les changements entre l’effet de composition et l’effet de comportement est assez simple. Pour l’effet de composition, on observe ce qui serait advenu du taux de participation si toutes les variables explicatives avaient changé, mais qu’on avait maintenu constants les coefficients estimés.