Fitting sinusoids to observations of rotating spotted stars
Abstract
It is assumed that K blocks (e.g. seasons) of observations are available, and the parameters
characterizing a fixed-frequency sinusoidal variability (mean light level, amplitude, phase)
are constant within each of the blocks. The paper is concerned with estimation when any
combination of these parameters varies between blocks of observations. This allows observations
subject to changes in mean light level, spot sizes and/or spot locations to be modelled.
Objective choices between competing models, and the calculation of the standard errors of
model parameters, are also dealt with. Illustrative applications to simulated and real data are
given.