Multiple schedule component duration: a reanalysis of Shimp and Wheatley (1971) and Todorov (1972).

Fields (1978) re-examined two older pigeon studies. The birds pecked keys under multiple VI schedules. Components lasted 30 s, 60 s, or 120 s.

The author checked if shorter parts lowered absolute response rates. Herrnstein’s equation predicts they should.

The numbers did not fit. Absolute rates stayed flat across durations. Shorter components did not cut responding.

The finding weakens a core matching-law claim.

Reiss et al. (1982) later showed duration can inflate rates, but only when richer reinforcement rides along. Strip that correlation and the effect vanishes. Their data extend the 1978 warning: look at reinforcer rate, not just clock time.

Jones et al. (1975) found matching of relative response to relative reinforcement duration, yet they used 5-s switches and two keys. The positive result sits beside L’s negative one because H measured relative, not absolute, rates.

Carr et al. (1985) directly compared 15-s and 60-s components and saw no sensitivity gap. Their null outcome lines up with L’s re-analysis: brief parts alone do not boost control.

When you build multiple schedules in the clinic, do not assume shorter components will automatically calm or boost responding. Check the reinforcer rate in each part first. If rates differ, control for that before you credit (or blame) the timer. This keeps your interpretations clean and your interventions precise.