We propose a panel data model for nonstationary variables with interactive fixed effects and coefficients that may vary over time and use it to examine time variation in the income elasticity of health expenditures in the OECD and the Eurozone. Our empirical analysis shows that the income elasticity of healthcare expenditure slightly increased in the OECD and the Eurozone during 1995–2004 but remained below one. This finding suggests that healthcare is not a luxury good in these countries.

中文翻译：

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经合组织和欧元区医疗保健支出随时间变化的收入弹性

我们提出了一种针对非平稳变量的面板数据模型，该模型具有交互式固定效应和随时间变化的系数，并用于检验经合组织和欧元区卫生支出收入弹性的时间变化。我们的经验分析表明，在1995年至2004年期间，经合组织和欧元区的医疗保健支出的收入弹性略有增加，但仍低于1。这一发现表明，在这些国家，医疗保健不是奢侈品。