A functional analysis of chained fixed-interval schedule performance.
Chained FI schedules create predictable pause patterns that follow the matching law.
01Research in Context
What this study did
Researchers put pigeons on chained fixed-interval schedules. Each chain had two links. The first link ended after a set time. The second link gave food after another set time.
They watched how long the birds paused before starting each link. They checked if the pauses matched the matching law.
What they found
The birds paused longer in the first link when the second link had a longer wait. Their response rates fit the matching law predictions.
Longer delays in the second link meant more waiting in the first link. This shows the birds could tell which link was which.
How this fits with other research
Edwards et al. (1970) showed pigeons learn simple FI schedules fast. This study adds that birds also learn chained FIs. The extra link does not break the pattern.
Wacker et al. (1985) found babies act like pigeons on FI schedules. But older kids use words to guide their timing. This shows the pigeon pattern holds until language kicks in.
Najdowski et al. (2003) let birds face daily changes in terminal-link delays. The birds shifted their initial-link pauses right away. This extends the 1974 finding to real-time schedule tweaks.
Why it matters
You can predict how clients will act on chained schedules. If the last step takes longer, expect more waiting at the start. Use this to set realistic goals and avoid frustration.
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02At a glance
03Original abstract
Three pigeons were trained on two-link chained fixed-interval fixed-interval schedules. Numbers of responses, time spent responding, and the total time spent in each component were measured. The data were analyzed according to the matching law for multiple and concurrent schedules. In most conditions, the ratio of response rates in the two links was a constant proportion of the ratio that would be predicted in a multiple schedule with the same components. Data on pauses during the interval schedules showed that, in most conditions, the pause duration was a linear function of the interval length, and greater in the initial link than in the terminal link. The experiment thus demonstrated a quantitative functional analysis of performance on a chained schedule.
Journal of the experimental analysis of behavior, 1974 · doi:10.1901/jeab.1974.21-323