Schedules of RFT

Schedules of RFT 1st way of categorizing ➔ Continuous RFT ◆ A reinforcement is given every single time ➔ Intermittent RFT ◆ A reinforcement is given only sometimes but not always 2nd way of categorizing ➔ What the reinforcement depends on ◆ Number of responses (ratio) ◆ Time + response (interval) ◆ rate: production of behavior as a function of time (DRL,DRH) 3rd way of categorizing ➔ Fixed Ratio (FR) ◆ A reinforcer is delivered after a number of responses that does not change ◆ FR6: the rat receives a RFT after pressing the lever 6 times (6:1) ◆ FR1: everytime the rat presses the lever, aka continuous ◆ Number of responses per consequences ◆ Break & Run ➔ Fixed Interval (FI) ◆ A reinforcer is delivered after the first response that occurs following a set amount of time ◆ Responses that happen within the interval do not matter but the time does not start over ◆ FI2’ meaning after 2 minutes the reinforcer is delivered after the first response ◆ Scallop ➔ Variable Ratio (VR) ◆ A reinforcer is delivered after a number of responses, but that number changes around some average ◆ VR5 - number of average ◆ Example: playing the lottery or essentially any gambling in general ◆ High steady rate behavior ➔ Variable Interval (VI) ◆ A reinforcer is delivered after the first response that occurs following a particular amount of time that changes around some average ◆ VI7’ the RFT being delivered after the first responses after the average of 7 minutes ◆ Example: Pop quizzes ◆ Steady state but moderate rate R-rate influences Why are VR’s Higher rate than VI? If I respond faster, do I speed up the RFT rate or do I do more work? VR VI RFT-rate Determine No influence - can’t change the time “Work” (Rs/rfr) No influence Determine - doing more work in the time Equate RFT-rate ➔ Yoked - behavior of one organism is going to determine the experience of another organism ➔ Two pigeon, pecking behavior of one on a VR schedule and pecking behavior of another on a VI schedule so we can equate RFT rate ➔ Start with VR schedule on the VR schedule ◆ VR12: Ratio requirements are ◆ 15 - 15” ◆ 9 - 3” ◆ 24 - 18” ◆ 3 - 1” ◆ 7 - 3” ◆ 17 - 15” ➔ Put the yoked bird on a VI schedule (both birds are getting RFT roughly at the same rate) ◆ 15” ◆ 3” ◆ 18” ◆ 1” ◆ 3” ◆ 15” ➔ Equating reinforcement still has a high VR and a moderate VI meaning RFT rate is not causing the difference Equate “work” ➔ Yoking VR to VI meaning yoked bird is VR and control bird is VI ➔ Measure how many responses a bird makes in the time intervals ◆ The VRs are now the those amount of responses in the VI schedule ➔ Equating “work” still has a high VR and a moderate VI meaning its not work another that is causing the rate difference Limited Hold Contingency ➔ Can be added to any interval schedule (FI or VI) ➔ Limited hold 3” on a VI schedule ◆ If you have a 30” interval, you have 3” to respond after the 30” passes, if you don’t the RFT goes away. ◆ Still a VI schedule but there is such thing as waiting too long ◆ The VI with a limited hold started to have a higher steady rate Superstitious Behaviors ➔ Our behavior does not control the outcomes ➔ Laltal - pigeons study ◆ Put pecking behavior on a VI (R-dep.) schedule ◆ Would change some of the intervals to a VT (R-ind.)schedule very very slowly ◆ They reduce their rate of responding almost perfectly. They are incredibly sensitive to whether their behavior is producing outcomes Source of variability ➔ On a VT there is variability in the amount of time between when the stimulus is delivered and when the last response occurred ➔ Delay of RFT Contingency ◆ An amount of time between the reinforcer and the response that produced it to a VI schedule ◆ If you add a 5” delay, then the rfr will be delivered after 5” of the response. This allows us to add a similar variability that's in a VT schedule Complex Schedules ➔ Single-R option ◆ Second-Order Schedule ● Completion of one basic schedule is treated as a single response unit that is then reinforced according to another basic schedule ● Findley & Brady (chimpanzees) ○ FR 4000 -> food (hopper light) ◆ Multiple Order Schedule (Mult) ● At least two basic schedule components, only one component is in effect at a time, the components alternate irregularly and a different stimulus is associated with each component. ● Red light: peck - grain (VR 12) ● Green light: peck -grain (FI 2’) ○ Behavioral contrast ◆ Under multiple schedules, when the reinforcement rate of one component changes, the response rate changes in the other component in the opposite direction. ➔ Multiple-R option ◆ Concurrent Schedules (CONC) ● Two available responses that can happen at any time and each response is associated with its own schedule of RFT. ● Left key: FR25 ● Right key: FR50 ○ Choose FR25 and settle on it because you get RFT faster and its less work ● Matching law ○ Given multiple response options an organism will distribute its behavior across the options in the way that equals the relative rate of RFTs ◆ Concurrent-Chain Schedules (CONC-Chain) ● A concurrent schedule that is followed by one or more additional schedule determined by the choice made in the initial concurrent schedule ● ● Self-Control (Rachlin & Green) ○