The Useful Science

While reading in "The Economist" about the preponderance of economic studies focused on the United States, I wonder about spending and the Keynesian notion that it doesn't matter how the money is spent, just that it is and it be massive.  A cursory google search got me to the "Failure of Obama Stimulus Package / Stimulating Economic Growth" by the  Heritage Foundation which uses my favorite example of Japan's massive spend in the 1990's to counter the huge asset deflation suffered earlier and which did nothing at all to avoid the lost twenty years and counting. I believe that massive spending in productive investment is the correct answer, but I can't prove it.  Who has a good study on that?