Can solar luminosity & activity be predicted? Can a star's luminosity and its activity, solar flares and sunspots, be predicted?

If so, with what accuracy &amp; precision?
All of these effects are related to the 11 year solar cycle. And while we know there are times when the sun is "active" versus "inactive" we aren't necessarily predicting exactly where sunspots or solar flares will occur, but how many we see in total.