How effective is quantitative easing in stimulating economic activity and raising inflation?

My main research contributions on this topic have now each been published.

Quantitative easing lowers Treasury and corporate bond yields, but the pass through to corporate bond yields is more modest than that associated with a lower federal funds rate: Kiley (2016)

As a result, overall financial conditions improve by less with quantitative easing than with similar movements in the federal funds rate: Kiley (2014a)

And this evidence is consistent with the more limited stimulus associated with long-term interest rates relative to short-term interest rates: Kiley (2014b)