A number of methodologies can be used to compare wages and incomes. Depending on which one is used, results can vary.
As for the method I used, I don't necessarily want to get into the technical details. Economists who compare wages usually use microdata. It's called the human capital earnings function. This tool completes a regression analysis of wages using such variables as education, experience, employment and other characteristics. We added language of work to the explanatory variables. We had controls on acceptable and reasonable differences in wages, and we were trying to see what impact the language of work had on wages.
For immigrants in Montreal, we did end up with the somewhat disappointing result that it was more profitable to work in English than in French. You have to understand that it's much harder for immigrants in Montreal. We want them to learn French, so we offer them French courses. However, when they enter the labour market, French is often not enough and they also need to learn English to function properly.
So Quebec is in a somewhat unique situation compared to the rest of Canada. In Toronto, there is only one language: Everyone has to learn English. On the other hand, in Quebec the government wants immigrants to learn French, and that's not always easy. They also have to learn English. Immigrants from francophone countries often have limited knowledge of English when they arrive. So it's a bigger challenge for Quebec than it is for the rest of Canada.