Volume 25 number 2 (1997)
Measurement of observable stars, variable or otherwise, is only part of the process of understanding their nature. First of all, quite a lot of theory-based analysis goes into a measurement of a desired basic property for the star (such as mass, radius, or luminosity). Second, theoretical models are used to check relationships amoung the observed parameters. Interpreted using models that also give consistent relations amoung the resulting properties of the star, can we say that we know what the properties of the star really are? We are not there yet for the Miras, although great progress has been made in recent years, both on the theoretical side and on the observational side.