Responding under chained and tandem fixed-ratio schedules.
Chain schedules create longer post-reinforcement pauses than tandem schedules of equal ratio size—stimulus sequence matters.
01Research in Context
What this study did
Jwaideh (1973) compared two ways to string fixed-ratio requirements together.
In the chained version each ratio link had its own signal light.
In the tandem version the same light stayed on for the whole chain.
The author watched how long subjects paused after food before they started working again.
What they found
The chained set-up created longer pauses than the tandem set-up.
When the light order was flipped the long pauses shrank right away.
The first light in the chain controlled most of the stopping behavior.
How this fits with other research
Long (1963) saw the same pause pattern with children ten years earlier.
That team added an external clock to shorten the wait when needed.
Thomson (1974) stretched the idea to fixed-interval links and still found the longest pauses in the first link.
Mazur (1983) later showed the pause, not the run speed, is what changes across ratio designs.
Together the papers say: put your hardest or longest requirement early and add a cue if you want to cut pausing.
Why it matters
If you run token boards or chained tasks the first link sets the tone.
Add a clear cue or timer to that first step to keep the momentum going.
You can flip the order for a quick pause fix without changing the work count.
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02At a glance
03Original abstract
The role of stimuli in chained fixed-ratio schedules of reinforcement was examined. At various ratio values, responding on schedules consisting of three or five equal components, with a different colored light in each component ("block counter") was compared with responding on tandem or simple fixed-ratio schedules having the same color present throughout the entire ratio. At all ratio values except the smallest, the chain stimuli resulted in longer pauses after reinforcement. The magnitude of this effect became greater as the size of the ratio was increased. Post-reinforcement pause durations were longer under five-component schedules than under three-component schedules. Running rates in the first component were lower on the chained schedules than on the tandem schedules; on both kinds of schedule, rates were lower in the first component than in the rest of the ratio. When the sequence of stimuli was reversed, the duration of the post-reinforcement pause dropped markedly and the running rate in the initial component increased, but these effects gradually disappeared after the first reversal session. When the final chain stimulus was substituted for the first component stimulus but continued to appear in the final chain component as well, the pause duration dropped and remained at this lower level during subsequent sessions.
Journal of the experimental analysis of behavior, 1973 · doi:10.1901/jeab.1973.19-259