A simple BASIC program to generate values for variable-interval schedules of reinforcement.
Grab this free BASIC script to create perfect VI schedules without hand-calculating Fleshler & Hoffman values.
01Research in Context
What this study did
The author wrote a short BASIC program. It spits out the exact wait times you need for a true variable-interval schedule.
You type in how many intervals you want. The program follows the old Fleshler & Hoffman math, but does it in seconds.
What they found
No new data. The paper simply gives the code. Anyone with a PC can now make VI schedules that keep the same odds of reinforcement at every moment.
How this fits with other research
Dugan et al. (1995) also built teaching software, but theirs helps students feel how schedules work. Pfadt (1991) just builds the schedule numbers.
Gilroy et al. (2017) updated the idea: they wrote modern R code for delay-discounting stats. Same spirit, newer language.
Valentino et al. (2024) created a calculator for scoring supervision. All four papers hand busy clinicians a ready-made tool so no one has to do long math by hand.
Why it matters
If you run VI sessions in the clinic or the lab, stop looking up tables. Download the 30-line BASIC file, run it, and paste the numbers into your protocol. You save prep time and guarantee constant-probability timing every session.
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02At a glance
03Original abstract
A BASIC program to generate values for variable-interval (VI) schedules of reinforcement is presented. A VI schedule should provide access to reinforcement with a constant probability over a time horizon. If the values in a VI schedule are calculated from an arithmetic progression, the probability of reinforcement is positively correlated with the time since the last reinforcer was delivered. Fleshler and Hoffman (1962) developed an iterative equation to calculate VI schedule values so that the probability of reinforcement remains constant. This easy-to-use program generates VI schedule values according to the Fleshler and Hoffman equation, randomizes the values, and saves the values in ASCII to a disk file.
Journal of applied behavior analysis, 1991 · doi:10.1901/jaba.1991.24-799