Beta Lyrae light curve changes

Some new data are tabulated. Most periodic variations that have been reported in the literature do not pass standard significance tests, according to our adopted criteria.

Certain other periods do pass the tests, although most do so only for one, or at most two, data sets. Our main findings are that a period of about 9 months is present in all data sets and that it connects extremely well in phase from era to era, all the way back to Baxendell's observations of 1840-1877. The semiamplitude is small but reasonably consistent, averaging about 2% of the flux in the light curve maxima.