 as my colleague so interestingly pointed out it's not a cumulative record it's a cumulative record my thought was yes air logs on a computer which ironically would be a cumulative record and a cumulative record at the same time but don't just it's bad anyway so cumulative record is what we're thinking of here this is a genuinely skinnish thing since he invented the cumulative recorder all right so the basic idea is really simple count behavior that's that so if I if I if I do one behavior right so I'm gonna wave at you hi so there's one baby I can wave it again now there's two behaviors I can wave it again now there's three way which again there's four way which again there's five you notice how my hand keeps going up well on a cumulative recorder it would do just that the little pen would begin tracking across the paper and it would just go up every time behavior happened it would take up right so it's it's a cumulative record of how much you behave not over a minute or something that is literally here's how much behavior this person or this organism has engaged in it's cumulative you're adding it all up right so cumulative record it's a useful very useful tool especially an experimental analysis of behavior or understanding rates of responding skinner invented this tool and the this is one of those situations that allowed him to actually understand the functions of schedules of reinforcement there's way more to it and you're gonna have to see a longer video for that goodbye