Individual and social discounting in a viscous population

Area of Science:

• Evolutionary Biology
• Behavioral Economics
• Ecological Modeling

Background:

• Social discounting, crucial for public policy, lacks a consensus on determining the social discount rate.
• Current economic models do not fully account for biological factors influencing intergenerational value judgments.

Purpose of the Study:

• To establish an evolutionary biological framework for understanding social discounting.
• To analyze the relationship between individual and social discount rates based on biological principles.

Main Methods:

• Modeling a patch-structured iteroparous population with limited dispersal.
• Analyzing trade-offs between immediate and delayed benefits within a community context.
• Investigating the impact of kinship and dispersal on social discount rates.

Main Results:

• The social discount rate is generally lower than the individual (private) discount rate.
• The disparity between social and private discount rates is amplified by low dispersal and low patch destruction rates relative to individual mortality.
• Enforced collective action increases social investment without altering the social discount rate.

Conclusions:

• An evolutionary biological perspective provides a novel framework for social discounting.
• Kinship and dispersal dynamics are key determinants of how societies value future outcomes.
• This framework offers insights into public policy decisions concerning long-term societal benefits and costs.