A sample of 102 local (0.02=<z=10^7^M_{sun} was selected from the Sloan Digital Sky Survey (SDSS) and observed using the Keck 10 m telescope to study the scaling relations between M_BH and host galaxy properties. We study profile changes of the broad H{beta} emission line within the three to nine year time frame between the two sets of spectra. The variability of the broad H{beta} emission line is of particular interest, not only because it is used to estimate M_BH_, but also because its strength and width are used to classify Seyfert galaxies into different types. At least some form of broad-line variability (in either width or flux) is observed in the majority (~66%) of the objects, resulting in a Seyfert-type change for ~38% of the objects, likely driven by variable accretion and/or obscuration. The broad H{beta} line virtually disappears in 3/102 (~3%) extreme cases. We discuss potential causes for these changing look active galactic nuclei. While similar dramatic transitions have previously been reported in the literature, either on a case-by-case basis or in larger samples focusing on quasars at higher redshifts, our study provides statistical information on the frequency of H{beta} line variability in a sample of low-redshift Seyfert galaxies.

Cone search capability for table J/ApJ/821/33/table23 (Observations, Seyfert-type Classification (table 2) and Results from Spectral Fitting (table 3))