Consistently or Randomly block every X incoming MIDI Notes?

Hello - can you help me with script(s) that allow me to block/throw out every "X" incoming midi note on messages?
If possible I'd like two blocking options (could be two scripts):
1. Block/throw out every "X" notes (e.g. every 2nd note, every 3rd note, etc).
2. Block/throw out notes randomly, based on a percentage chance.  (e.g. 33% chance a note will be tossed, 75% chance a note will be tossed).

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*Why would I want to do this?  I have a device that generates MIDI based on changes in current in a houseplant.  At low-sensitivity there's still too much data coming in.  

Thanks in advance!

UPDATE:   
For #2:  I can understand just enough of the post Drum hits with probabilit to believe this might satisfy #2 (50% example):
# trap note on
if MT == 90
if R2 == 0 # R2 will return 0 or 1
block
end
end
To me, it looks like MT == 90 might be "MIDI Note On", and R# provides a random number between 0 and the # (HEX) numeral you put after R.

Also, this post looks useful but I don't understand where/how to set the percentage:  Probability of Note Passing