Appendix and Data for "The intimate link between income levels and life expectancy: Global evidence from 213 years"

This fileset contains the appendix and replication data for the paper entitled "The intimate link between income levels and life expectancy: Global evidence from 213 years" published in Social Science Quarterly by Michael Jetter, Sabine Laudage and David StadelmannAbstract: Objectives - What is the main driver of life expectancy across societies and over time? This study aims to document a systematic and quantitatively sizeable relationship between income levels and life expectancy. Method - Using different regression methods and robustness tests, a panel dataset of 197 countries over 213 years is analyzed. Results - By itself, GDP per capita explains more than 64 percent of the variation in life expectancy. The Preston curve prevails, even when accounting for country- and time-fixed effects, country-specific time trends, and alternative explanatory variables, such as health care expenditure, malaria prevalence, or political institutions. If anything, this link has become stronger over recent decades when data quality has improved. Results from instrumental variable estimations suggest this finding to be largely unaffected by reverse causality. Quantile regression results suggest the relationship between income and life expectancy to be persistent across different levels of life expectancy. Conclusions - Income matters for life expectancy. If policymakers want to prolong people's lives, economic growth appears to be the predominant medicine.本数据集包含迈克尔·杰特（Michael Jetter）、萨宾·劳达格（Sabine Laudage）与戴维·施塔德尔曼（David Stadelmann）发表于《社会科学季刊》（Social Science Quarterly）的论文《收入水平与预期寿命的紧密关联：来自213年的全球证据》的附录与复现数据。 摘要： 研究目标——不同社会及不同时期下，预期寿命的核心驱动因素是什么？本研究旨在揭示收入水平与预期寿命之间存在系统性且量化规模可观的关联。 研究方法——本文采用多种回归方法与稳健性检验，对涵盖197个国家、跨度213年的面板数据集（panel dataset）展开分析。 研究结果——仅人均国内生产总值（GDP per capita）一项即可解释超过64%的预期寿命变异。即便在控制国家与时间固定效应（fixed effects）、国家层面时间趋势，以及医疗支出、疟疾患病率、政治制度等其他解释变量的情况下，普雷斯顿曲线（Preston curve）依然成立。随着近几十年来数据质量提升，该关联反而愈发显著。工具变量估计（instrumental variable estimations）结果显示，该结论基本不受反向因果关系的影响。分位数回归（quantile regression）结果表明，收入与预期寿命的关联在不同预期寿命水平下均保持稳定。 研究结论——收入水平对预期寿命存在显著影响。若政策制定者希望延长民众寿命，经济增长或将是最为有效的手段。