Stefano,
Yes, all the stock factors could be added to the Ranking Systems, IF, you want to develop a private one or one that works for only a small part of the community.
The Ranking Systems rank all the stocks, and each individual can or will only buy a select range of stocks that meet his/her investing style. Many factors like MktCap, Price, AvgVol, AvgDailyTot, etc, need to be selected with respect to what each member is comfortable with and can or should buy.
It is VERY time consuming to develop a new Ranking System that meets personal goals and have that system even come close to the performance of many of the public systems. I think that the time is better spent testing new factors added to existing systems that might improve a system’s performance, and time spent optimizing the weightings of a system’s factors.
It takes enough time for me to develop good, well thought out Buy and Sell Rules that meet my needs.
I am using 8 different Ranking Systems. I can’t imagine the time it would take to add those factors to 8 ranking Systems and get them to perform nearly as well as my Sims do now. It is just far easier and faster (lazy? OK, I’ll go with lazy) to develop personal Sims than personal Ranking Systems.
Denny