Before revision:  In other words,  there are events of small probability that  can give rise to systemic default cascades sparked by a devaluation of the common exposures and amplified by herd behaviour .
After revision:  In other words, sparked by a devaluation of the common exposures, there are events of small probability that can give rise to systemic default cascades sparked by a devaluation of the common exposures and amplified by herd behaviour .