I am curious and want to do some personal research into alpha signals, but I couldn't find much relevant information. What I think will be the way to is to start with a return series, build a long- short portfolio (e.g. top/bottom decile or some more refined ML techniques), take those returns calculate z-scores and do s.th like
z-score * IC * volatility
to get a real alpha signal that I can use in a portfolio optimisation context. Would be great to get more insight.