Concurrent progressive-ratio and fixed-ratio schedule performance under geometric and arithmetic progressions by...

Area of Science:

• Behavioral Economics
• Animal Behavior
• Operant Conditioning

Background:

• Understanding food demand is crucial in behavioral economics and animal welfare.
• Progressive-ratio schedules are used to measure the reinforcing effectiveness of commodities.
• Comparing different schedule types and progression methods can refine demand assessment.

Purpose of the Study:

• To compare food demand in brushtail possums under concurrent progressive- and fixed-ratio schedules.
• To evaluate the impact of geometric versus arithmetic schedule progressions.
• To assess the efficiency of within-session versus across-session incrementing ratios.

Main Methods:

• Twelve brushtail possums were exposed to 16 experimental conditions.
• Schedules included geometric (base 2) and arithmetic (step 5) progressions.
• Food types tested were a flaked barley/coco-pop mix and rolled oats.

Main Results:

• Overall performance was similar across within- and across-session incrementing schedules.
• Geometric and arithmetic progressions yielded similar demand accounts for most subjects.
• Six possums preferred rolled oats; two preferred the flaked barley mix.

Conclusions:

• Incrementing ratios within sessions using an arithmetic progression is time-efficient.
• This efficient method allows for investigating food demand without altering conclusions.
• Results provide insights into food preference and demand elasticity in possums.