positive externalities -merit good

healthcare

Vaccination has public good characteristics: herd immunity is non excludable (benefit everyone) and non rivalrous

Individuals under consume because they don’t capture the full social benefit

Public goods

Non excludable (benefit everyone) and non rivalrous (free rider problem)

Under consumed because of information failure or consumers undervaluing positive externalities

Higher education

Research finding non rivalrous (your use doesn’t reduce mine) university research create spillovers beyond the institution justifies public spending on research

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