Yes.
It is kind of standard practice now for governments that are negotiating free trade to commission an economic study, as was done in the Canada-Japan case, based on the use of what's called computable general equilibrium models, or CGE, which is the acronym in economics. I actually worked with CGE models in my doctoral dissertation, so I'm one of a handful of Canadians who can actually understand how those things work.
In essence, the model is a set of mathematical equations. Each equation is intended to capture mathematically an assumed relationship between different industries, supply and demand forces, and so on. What happens is these modellers will take a CGE model, calibrate it to describe a certain set of data, and then shock the model to simulate the impacts of a reduction in tariffs or other trade barriers, and then the resulting change in the model's solution is held to represent the benefits resulting from the free trade agreement.
You're quite right, Mr. Davies, to highlight that. What comes out of the model is only as good as what goes into the model, in the sense of the assumptions and relationships that are built into the model's equations. Almost without fail, the CGE models incorporate the assumption of full employment, which is that no one can be laid off, the assumption of no capital mobility, which is that capital cannot flee a country looking for a lower-cost-of-production jurisdiction, no impact from exchange rates or other nominal variables, and they usually assume—