Welcome to The Nonlinear Library, where we use Text-to-Speech software to convert the best writing from the Rationalist and EA communities into audio. This is: Comparison between the hedonic utility of human life and poultry living time, published by Vasco Grilo on June 8, 2022 on The Effective Altruism Forum.
Summary
This analysis estimates the negative utility of poultry living time as a fraction of the utility of human life, under total hedonic utilitarianism (classical utilitarisnism).
The results are presented by country in this spreadsheet (see tab "TOC").
The conclusions are very sensitive to the moral weight of poultry birds relative to humans, and the quality of their living conditions in factory farms relative to fully healthy life. However:
In expectation, the (mean) negative utility of poultry living time seems much larger than that of human life.
Realistically, the (median) negative utility of poultry living time seems comparable to that of human life.
You can use this Guesstimate model to select your preferred inputs.
Acknowledgements
Thanks to Cynthia Schuck-Paim, Jason Schukraft, Lewis Bollard, Matt Sharp, Michael St. Jules and Scott Smith for feedback.
Methodology
The logic of the calculations is illustrated in this Guesstimate model. The tabs mentioned throughout the following sections refer to this spreadsheet.
Utility of human life
The utility of human life (QALY/person/year) was determined from the ratio between the healthy and full life expectancy. This is imperfect, but allows to estimate the utility of human life via a linear regression on life expectancy at birth:
The utility of human life was calculated through the mean life expectancy at birth of the years between 2025 and 2100 (see tab "Future utility of human life").
Data about the future life expectancy at birth was taken from OWID, and is in tab "Future life expectancy".
The linear regression coefficients were calculated based on data about the healthy and full life expectancy at birth from 1990 to 2016 (see tabs "Utility of human life and life expectancy" and "Past utility of human life").
Data about the past healthy life expectancy at birth was taken from OWID, and is in tab "Past healthy life expectancy".
Data about the past life expectancy at birth was taken from OWID, and is in tab "Past life expectancy".
Utility of poultry living time
The utility of poultry living time per capita (-QALY/person/year) is the product of:
The poultry living time per capita (pyear/person/year), which is the product between:
The poultry production per capita (kg/person/year).
The ratio between poultry living time and production (pyear/kg).
Moral weight of poultry (QALY/pQALY).
Quality of the living conditions of poultry (-pQALY/pyear).
The factors defining the poultry living time per capita were modelled as constants, and the ones regarding the moral weight and quality of the living conditions of poultry as distributions. The following sections provide further details.
The calculations of the utility of poultry living time per capita by country were performed in this Google Colab program, and the respective results uploaded to the tab "Utility of poultry living time per capita".
Poultry production per capita
The poultry production per capita between 2025 and 2100 (kg/person/year) was determined from the time-weighted average of those of the following periods:
2025 to 2050: mean between the poultry production per capita in 2025 and 2050.
2050 to 2100: half of the poultry production per capita in 2050.
The poultry production per capita in 2025 and 2050 was estimated from the ratio between the poultry production and population. The poultry production was calculated considering:
The poultry production by country in 2018 from OWID (see tab "Poultry production").
The poultry production annual growth rate by region, which was estimated by adding the following (see tab "Poultry production annual growth rate"):
Poultry population annual growth rate between 2005/2007 an...