Hi Alexander,
I think it's pretty neat you're using integer values between -3 and +3 for your values in the analysis field.
It's a divergent field with normal at zero, kind of like cool, cold, freezing on the left side and warm, hot, burning on the right side.
Depending on how you classify it, your data can be:
Ordinal: the data can be categorized and ranked.
Interval: the data can be categorized and ranked, and evenly spaced.
Why don't you run it and see what happens, report back, and enlighten us.
You're still going to need a minimum of 30 samples. I'm hoping you have lots more.
What I like about "optimized" hot-spot is it adjusts the neighborhood distance so you get meaningful results.
Please just don't break the internet, ok?
RSVP - Thanks!