"to test how to reach 5 stocks every month" with 2 overlapped screens.

I'm not sure the sum of the rankings gets us what we want, which was to start off with the stocks that are in both screens, regardless of their ranking in their screen, then fill in with the stocks that are not common.

The overlap screen that musselmant posted does not always have 5 stocks, sometimes it is heavily weighted to just 1 or 2 stocks. Makes it impossible to compare that with your rankSum screen. We are already having a small number of stocks. In Jim's various sum-of-ranks screens he has 20 or 25 stocks, so much less risky, only 4%-5% each instead of 20%.

The ranking criteria in the two screens are different, so there is no reason to prefer the #2 ranked stock in one screen to the #4 ranked stock in the other.

The problem is how to decide to fill in after the common stocks.

First, obviously, take the PHL stocks that are also in RS. That gets you the common stocks regardless of their rankings in their own screen. The #1 in one screen may be the #5 in the other. If both screens say a stock is good, then it is probably very good.

You could fill in with the PHL stocks that are *not* in RS, or vice versa. But that feels unsatisfying, as it would fill in with the non-overlap stocks exclusively from one screen or the other.

It seems reasonable -- and easy -- to just pick the non-common stocks alternately from each screen (in rank order), until you've got 5 stocks total.

I have no idea how to backtest any of this in GTR1.

Frankly, I am almost inclined to run an overlap screen with 10 stocks selected from the top 10 of the PHL and RS screens, while keeping those screens at 5. Just because in total we will not be so concentrated in a small number of stocks. That will lessen the pain of the days when, for example, SNDK loses -14% and MU loses -10%. Because those two stocks are in all 3 screens.