This study applies recurrent event analysis to examine the determinants of changes in firm credit ratings. This study uses two extended Cox proportional hazard models to examine upgrade and downgrade data separately. Explanatory variables are taken from financial ratios in Z-score (Altman, 1968)...

A study of the use and improvement of Hull and White's (1988) control variate technique in pricing options is provided. It contributes to the literature in two ways. First it is shown that it is not optimal to use the entire error of a control variate against its known price (usually a...