fractional variability corrected for measurement error, as defined by Rodríguez-Pascual et al. (1997), and , the ratio of maximum to minimum flux, respectively. Both  and   parameters are affected by contamination of the measured quantities by constant-flux components; the optical continuum values are somewhat diluted by the constant contribution of the underlying host galaxy, and the emission-line values are affected by both narrow-line contributions and probably slowly varying  emission as well. In any case, these will have only a modest effect on  and  and inspection of Table 3 shows clearly that the large-amplitude, rapid variations that characterize X-rays in NLS1s are much less pronounced in the optical spectrum.

While there is a clear lack of correlated short time-scale behavior of the X-ray and optical continua, the light curves in Fig. 1 suggest that a correlation on longer time scales is possible. To test this quantitatively, we have suppressed the rapid variations by smoothing both the optical continuum and X-ray light curves with a rectangular function of width 30 days, as shown in Fig. 3, similar to what was done by Maoz, Edelson, & Nandra (2000) in a comparison of X-ray and optical variability in the Seyfert 1 galaxy NGC 3516. Cross-correlation 