應用個體經濟之三篇研究

Abstract

本論文包含了三篇應用個體經濟之研究。第一篇文章為政治經濟學之研究, 第二與第三篇文章則為健康經濟學之研究。 第一篇文章使用台灣2004-2008年之各區每周收視率資料, 檢視新聞節目之政治傾向和正確度對消費者選擇新聞節目的重要性。我們發現, 泛藍之新聞節目在泛藍比例較高地區的收視率較高。此外, 我們發現在特殊政治事件發生時, 收視觀眾的政治偏好組成更為極端化。這個結果除了並非來自於反向的因果關係, 更顯示出消費者傾向收看與自己政治意識形態相近之新聞節目。最後, 本文使用兩個假新聞事件, 探討消費者對新聞正確度的敏感度。我們發現假新聞事件對收視率的影響極小, 甚或不顯著。 第二篇文章利用台灣1950年代瘧疾根除計畫, 探討早期(胚胎與嬰兒時期)暴露於瘧疾風險之長期影響。 我們合併1992-2012年台灣社會變遷調查所提供之個人資料, 與其出生時間和地點之瘧疾嚴重度資料。透過差異中之差異法(difference-in-differences), 本文發現瘧疾根除計對男性的教育程度與家庭所得具有正向的影響。我們亦使用台灣1980年戶口普查資料進行分析, 同樣發現瘧疾根除計畫之後, 教育程度有了顯著的增加。此外, 我們發現瘧疾根除計畫對男性其配偶的教育程度亦產生正向的影響。最後, 分量迴歸分析結果顯示, 瘧疾根除計畫之影響主要集中於低所得者。本文結果顯示早期暴露於瘧疾風險將對個人產生負面的影響。 最後一篇文章探討胚胎時期暴露於空氣汙染風險對台灣新生兒健康之影響。我們使用2001-2011年之出生通報資料與2000-2011年之空氣品質資料, 並透過工具變數法以減輕內生性所造成的估計偏誤, 來檢視胚胎時期健康狀況之影響。利用大氣溫度, 濕度, 以及雨量作為空氣汙染之工具變數, 我們發現胚胎時期暴露於懸浮微粒(PM10)使得新生兒早產, 體重過輕, 以及出生健康狀況不佳之機率皆提高。此外, 二氧化硫(SO2)與二氧化氮(NO2)亦使得新生兒早產與體重過輕(懷孕週數限於37至44週)之機率增加。本文結果顯示胚胎時期暴露於空氣汙染風險將對新生兒健康造成不利的影響。

This dissertation consists of three essays on Applied Microeconomics. The first essay contributes to political economics, and the second and third essays contribute to health economics. The first chapter (with Chun-Fang Chiang) investigates the role of news slant and news accuracy in consumers' choices of TV news programs in Taiwan. Using weekly audience ratings data from different regions in Taiwan between 2004 and 2008, we find that news programs leaning toward the Pan-Blue parties had more viewers from areas with more Pan-Blue supporters. Moreover, we find that consumers were more politically segregated in choosing news programs during political events than on ordinary days. The finding cannot be explained by reverse causality and suggests that consumers are inclined to watch news programs with a political ideology that approximates their own. Regarding consumer preferences for news accuracy, we examine changes in viewership caused by two well-known false news scandals involving reports that provided erroneous information. We find that the effects of these two incidents were either small or insignificant. The second chapter (with Ming-Jen Lin) utilizes the eradication campaign in Taiwan in the 1950s to estimate the long-term impacts of early-life (in utero and postnatal) exposure to malaria. Matching adults in the 1992 -- 2012 Taiwan Social Change Survey to the malaria intensity in their individual place and year of birth, difference-in-difference estimation shows strong evidence that the eradication increased men's own educational attainment as well as their family income in adulthood. We also use the 1980 census data to show there was a sharp education increase after the eradication. Furthermore, the eradication increased the educational attainment of married men's spouses. Finally, quantile regressions show that the effect concentrated on the lower percentile of the income distribution. Overall, our results suggest negative effects of early-life exposure to malaria. The last chapter (with Ming-Jen Lin) examines the health effects of air pollution during pregnancy on newborn babies in Taiwan. Using the birth data from 2001 to 2011 and data on atmospheric condition from 2000 to 2011, we examine the effects of in utero health conditions through the instrumental-variable (IV) method to address potential endogeneity problems. We use variation in temperature, humidity, and rainfall to instrument for in utero exposure to air pollution. We find that the increase in exposure to PM10 during pregnancy resulted in prematurity, low birth weight, and being born in bad health. Moreover, exposure to SO2 and NO2 during pregnancy led to prematurity and low birth weight for those born between 37 and 44 weeks of gestation. Our results suggest that air pollution had negative health effects on newborn babies.