Before revision:  We assess the size and power of the backtests in realistic sample sizes, and in particular demonstrate the tradeoff between power and specificity in validating quantile forecasts  .
After revision:  We assess the size and power of the backtests in realistic sample sizes, and in particular demonstrate the tradeoff between power and specificity in validating quantile forecasts L of ten bank trading portfolios. For some portfolios, test results depend materially on the choice of kernel .