Fixed-Interval Schedule
Also called: FI schedule, FI
Definition
A schedule in which the first response after a set amount of time has passed is reinforced — FI 2 minutes means that after two minutes, the next response earns reinforcement. Responses before the interval ends do nothing. It typically produces little responding early in the interval and an increase as the end approaches.
In plain language
After a set amount of time, the next response is rewarded. Responses before the time is up do nothing, so behavior tends to pick up as the time nears.
Example
A teacher checks on a student every five minutes and praises on-task work if she sees it then. Work picks up shortly before each check.
Not fixed-interval schedule
Praise for every fifth completed problem regardless of time. That is a ratio schedule.
Commonly confused with
See also
Written from
- ferster-skinner-1957
Written from Ferster and Skinner (1957). No textbook glossary consulted.
This entry has not yet been through clinical review. Treat it as a draft.