We study skill- and income-related differences in the access to health care as drivers of longevity inequality from a theoretical life-cycle as well as from a macroeconomic perspective. To do so, we develop an overlapping generations model populated by heterogeneous agents subject to endogenous mortality. We model two groups of individuals for whom differences in skills translate into differences in income and in the ability to use medical technology effectively in curbing mortality. We derive the skill- and age-specific individual demand for health care based on the value of life, the level of medical technology and the market prices. Calibrating the model to the development of the US economy and the longevity gap between the skilled and unskilled, we study the impact of rising effectiveness of medical care in improving individual health and examine how disparities in health care utilisation and mortality emerge as a consequence. In so doing, we explore the role of skill-biased earnings growth, skill-bias in the ability to access state-of-the art health care and to use it effectively, and skill-related differences in health insurance coverage. We pay attention to the macroeconomic feedback, especially to medical price inflation. Our findings indicate that skill-bias related to the effectiveness of health care explains a large part of the increase in the longevity with earnings-related differences in the utilisation of health care taking second place. Both channels tend to be reinforced by medical progress.

從一九九0年代開始，由於微電子、電腦、衛星通信、網際網路、光學纖維等資訊科技的發展，不僅造成社會生活的變遷，也帶動了國家競爭的新形勢。 在這樣的時代環境下，資訊知識發展與科技運用成為經濟發展成功的關鍵，唯有促使科技出現重大突破，才能提昇產業的競爭力。 在學術界，討論資訊科技的文獻上出現了生產力矛盾(productivity paradox)的說法，即他們發現使用資訊科技對於生產力的提升出現了不顯著甚至是負的結果。針對此，後續有許多學者提出各種解釋生產力矛盾的原因，諸如過度投資(overinvestment)、衡量錯誤 (mismeasurement)等問題。 因此，本研究以生產力指標中的總要素生產力為衡量對象，檢視資訊科技對台灣製造業是否具有矛盾的情形，並觀察當技術革新時，對人力資本的需求變化，資料期間為1995-2002年，採用的計量模型為揉合資料（pooling data）模式。 根據實證結果，自動化設備的應用出現生產力矛盾(productivity paradox)的情形，而人力資本對總要素生產力的貢獻則為顯著的正值，若觀察投入自動化生產設備對人力資本的需求，則發現有資本與技術互補（capital-skilled complementarity）的情形。因此推論：單獨增加自動化設備並無法提升總要素生產力，唯有透過自動化設備投資與人力資本的配合，兩者互補之下，以提升台灣製造業生產力。

Esta tesis doctoral es una colección de tres artículos. Los capítulos 1 y 2, co-autorados con Joachim Voth, investigan por qué Europa en 1700 ya era más rico que el resto del mundo y por qué Inglaterra fue el primer país en industrializarse. Encontramos que las dinámicas de la población, en lugar del crecimiento de la productividad, fueron los promotores más importantes del desarrollo económico de Europa Occidental durante la temprana edad moderna (1450-1700). Calibramos un modelo probabilístico para representar Inglaterra en 1700 y encontramos que ingresos iniciales más altos unidos a limitaciones de fertilidad aumentaron la probabilidad de industrialización. En el tercer capítulo, presento un nuevo hecho estilizado y analizo su contribución al sesgo del cambio tecnológico hacia los trabajadores más cualificados: El porcentaje de trabajadores cualificados en la producción intermedia está altamente correlacionado con la proporción de trabajo cualificado en la producción final. Esto genera un efecto multiplicador que refuerza la demanda de trabajo cualificado a lo largo de la cadena de producción. El efecto es importante, explica más de un tercio del aumento de la demanda de trabajadores cualificados en la industria manufacturera de EE.UU. / This dissertation is a collection of three essays. Chapters 1 and 2, co-authored with Joachim Voth, investigate the question why Europe in 1700 was ahead of the rest of the world and why England was the first country to industrialize. We find that population dynamics, rather than productivity growth, were the most important drivers for Western Europe to overtake China in the early modern period (1450-1700). We calibrate a probabilistic model to match England in 1700 and find that higher initial per capita incomes together with fertility limitation increased its industrialization probabilities. In the third chapter, I present a novel stylized fact and analyze its contribution to the skill bias of technical change: The share of skilled labor embedded in intermediate inputs correlates strongly with the skill share employed in final production. This delivers a multiplier that reinforces skill demand along the production chain. The effect is large, accounting for more than one third of the observed skill upgrading in U.S. manufacturing.