(cnt_r_bet_bluff / cnt_r_bet_known) * 100
this is how it is done. but I dont know how to see the definition of bet bluff.
As I read in pt4 forum, this stat is taking into account mostly high cards, low pairs etc. Yeah it is actually very tough to analyse what is bluff on river unless we take into consideration whole ranges, which is impossible for hud to calculate so fast.
So this stat is likely very unprecise. I often turn hands into bluff if I think it is max EV, so likely pt4 thinks I didnt bluff.
Also stat as W$SD is not much usefull, because it could be that villian was bluffing once 9/10 times for smaller pots and lost, and that he didnt bluff once for big pot and won. Or that he was only value betting but had worse hand. So imo all those stats are only usefull if they are very extrem, to recognize if someone is super agro or doesnt bluff at all.
"leads river on checked turn" also imo doesnt tell much unless extreme. Here we even need to consider preflop to turn stats because it could be that villian never bluffs turn and thus has low cbet turn % but bets river 100%.