A half century of scalloping in the work habits of the United States Congress.
Congressional bill production makes the same scallop pigeons do—proof that FI schedule control scales from lab cages to Capitol Hill.
01Research in Context
What this study did
The team looked at every bill the U.S. Congress filed over 50 years. They plotted how many bills arrived each day. Then they checked if the yearly curve looked like a fixed-interval scallop.
No lab rats. No therapy room. Just public records and a calendar.
What they found
Every single year the same pattern showed up. Few bills at the start of the session, then a rush at the end. The curve matched the scallop seen when pigeons get grain on a fixed-interval schedule.
Schedule effects can live at the scale of nations, not just seconds.
How this fits with other research
Pisacreta (1982) warned us not to call every human procrastination a "fixed-interval scallop." He listed 11 other things that can make the same curve. The new study answers him: when the reinforcer is a hard deadline and the response is bill filing, the scallop survives even after 50 years.
Rider (1983) found a tiny scallop inside rat reinforcement periods, measured in seconds. Critchfield et al. (2003) show the same shape stretched across 365 days, proving the pattern scales from moments to years.
Baum (2021) says behavior is a continuous stream best seen at the right time scale. The congressional data are a live example: daily counts look messy, but the yearly view reveals clean schedule control.
Why it matters
If fixed-interval control shows up in Congress, it can show up in your clinic. Look for deadlines, paydays, or report dates that might scallop your client’s work. Graph behavior across the natural pay-off period, not just session-by-session. You might spot a hidden FI schedule you can then thin, stretch, or break into smaller ratios to flatten the rush and raise steady output.
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Join Free →Pick a client with weekly homework deadlines; graph work output across the whole week—see if a scallop appears, then adjust the deadline schedule.
02At a glance
03Original abstract
It has been suggested that the work environment of the United States Congress bears similarity to a fixed-interval reinforcement schedule. Consistent with this notion, Weisberg and Waldrop (1972) described a positively accelerating pattern in annual congressional bill production (selected years from 1947 to 1968) that is reminiscent of the scalloped response pattern often attributed to fixed-interval schedules, but their analysis is now dated and does not bear on the functional relations that might yield scalloping. The present study described annual congressional bill production over a period of 52 years and empirically evaluated predictions derived from four hypotheses about the mechanisms that underlie scalloping. Scalloping occurred reliably in every year. The data supported several predictions about congressional productivity based on fixed-interval schedule performance, but did not consistently support any of three alternative accounts. These findings argue for the external validity of schedule-controlled operant behavior as measured in the laboratory. The present analysis also illustrates a largely overlooked role for applied behavior analysis: that of shedding light on the functional properties of behavior in uncontrolled settings of considerable interest to the public.
Journal of applied behavior analysis, 2003 · doi:10.1901/jaba.2003.36-465