This dissertation consists of three chapters which as a whole address development issues in Nigeria. These chapters relate to issues on conflicts, rural labor, education, weather shocks, health, and aid. Chapter 1 studied the effects of conflicts on the labor adjustment patterns of rural households in Northern part of Nigeria. I relied on variation in the conflict incidence and employed the use of instrumental variable technique in order to identify the effect of conflict on several household labor variables. The result reveals that conflict within 20km radius of household has led to adjustment of labor away from agriculture to nonagricultural sectors. Also, it has led to substitution of household agricultural labor with hired labor. The demand pressure on hired labor was also found to have increased the wage rates of agricultural hired labor. Chapter 2 investigates the effects of conflicts, depending on the nature, on educational attainment of individuals in Nigeria. Specifically, I looked at how two forms of conflicts with different nature and perpetrators - Boko Haram insurgence and Farmers and Herders conflict – affects educational attainments in Nigeria. I employed the Difference-in-Difference (DiD) technique and found that both forms of conflict hurts completed years of education of individuals that are exposed to them. However, the magnitude of the effects of farmers and herders conflict tends to be larger than that of boko haram insurgence. Chapter 3 studies the effectiveness of World Bank aid projects in reducing the adverse effects of weather shocks on children’s health in Nigeria. The study revealed that children’s’ exposure to weather shocks in their month of birth and in utero have adverse effects on their Weight-to-age- z-score (WAZ) and height-to-age z-score (HAZ). However, the availability of aid projects within 20km radius of these children helps to reduce such negative effects of such weather shocks.

京都大学 / 0048 / 新制・課程博士 / 博士(経済学) / 甲第18638号 / 経博第500号 / 新制||経||271(附属図書館) / 31552 / 京都大学大学院経済学研究科経済学専攻 / (主査)教授 照山 博司, 教授 柴田 章久, 准教授 敦賀 貴之 / 学位規則第4条第1項該当 / Doctor of Economics / Kyoto University / DGAM

Prior research on intra-firm pay disparity suggests intra-firm pay disparity at various hierarchy levels affects firm performance and executive-level pay disparity is related to investment risk in the credit and the equity market. However, none of the studies examine the relationship between CEO-to-worker pay disparity and credit investment risk. The purpose of this study is to investigate the association between CEO-to-worker pay disparity on credit investors' risk assessments. Large CEO-to-worker pay disparity could suggest CEO rent extraction which increases credit risk or effective labor cost management that decreases credit risk. Overall results of this study indicate increased CEO-to-worker pay disparity is associated with a lower cost of debt (a higher probability of credit rating upgrades). This association weakens as the growth rate of average employee pay increases and is more pronounced for labor-intensive firms than for capital-intensive firms, suggesting credit investors incorporate the information about the effectiveness of labor cost management in CEO-to-worker pay disparity in their risk assessments. In addition, the negative relationship between the change in CEO-to-worker pay disparity and the change in the cost of debt is less salient when CEO compensation increases rapidly. Further analysis shows the association is attenuated by increased excessive CEO compensation. The findings indicate credit investors also consider the risk arising from CEO rent extraction when they evaluate CEO-to-worker pay disparity. / Ph. D.

This thesis is an effort to advance our knowledge and understanding of the role that labor plays in shaping corporate financial policies and how it is in turn affected by considerations related to firms' financing. I present three essays on the interaction between finance and labor. First, I provide two examples of how labor affects financial decisions, in which I investigate the impacts that commitment to employee welfare and reliance on skilled labor have on cash management policies. Next, I examine the effect of ownership structure on labor investment decisions as an example of how finance affects human capital. In the first essay, I examine the relation between employee welfare practices and corporate cash holdings. Consistent with the predictions of the stakeholder theory, I find firms that are strongly committed to employee welfare, measured by ratings on employee relations, to hold more cash. The effect of employee welfare standards on cash holdings is stronger for firms in human-capital-intensive, competitive, and low turnover industries in which employees are more important to their businesses. The findings highlight the importance of human capital and employee-friendly practices as an overlooked determinant of cash holdings and suggest that managers can use cash to signal their financial health to current and potential employees, thereby increasing their competitiveness in labor markets. The second essay examines whether a firm's dependence on skilled labor affects its cash holdings. Consistent with a precautionary motive to accumulate cash when higher labor adjustment costs slow a firm's labor demand reaction to cash flow shocks, I find robust evidence that companies with higher shares of skilled labor hold more cash. The effect of skilled labor on cash holdings is more pronounced for firms that are financially constrained, attach higher values to their human capital, operate in competitive product markets, and belong to industries characterized by high labor mobility. The findings suggest that labor heterogeneity, and in particular the skill level of workers is an important determinant of corporate cash policies. The results provide managers of firms, particularly those that are financially constrained, with insights on how to minimize their labor adjustment costs and reduce the risk of losing their valuable human capital. In my third essay, I examine whether the presence of long-term institutional investors, who typically have strong monitoring incentives, can help mitigate agency conflicts associated with firms' employment choices. I find that abnormal net hiring, measured as the absolute deviation from net hiring predicted by economic fundamentals, decreases in the presence of institutional investors with longer investment horizons. Firms dominated by long-term shareholders reduce both over-investment (over-hiring and under-firing) and under-investment in labor (under-hiring).The monitoring role of long-term investors is more pronounced for firms facing higher labor adjustment costs. These findings suggest that institutional investors play an important role in firm-level employment decisions.

A partir de un modelo de ajuste dinámico en el mercado laboral se estiman costos de movilidad intersectorial del empleo para Argentina durante el período 1996-2009, siguiendo la metodología desarrollada en Artuç, Chaudhuri and McLaren (2010). Considerando los parámetros estimados se computan simulaciones para evaluar el impacto potencial de shocks comerciales y tecnológicos sobre la asignación sectorial del empleo, los salarios sectoriales y el bienestar de los trabajadores. Nuestros resultados indican la presencia de altos costos de ajuste en el empleo, lo que implica un ajuste lento en el mercado de trabajo como respuesta a shocks tecnológicos y comerciales. Encontramos que los costos son mayores para los trabajadores no calificados respecto de los trabajadores semi calificados, no difieren entre el sector del país que comprende al Gran Buenos Aires y la Región pampeana respecto al resto del país y presentan una estructura sectorial similar a la hallada por Artuç et al. (2010) para Estados Unidos. / This paper estimates workers’ intersectoral switching costs based on a dynamic model of labor adjustment using data for Argentina (1996-2009). The estimated parameters are incorporated into a neoclassical model of trade to simulate the dynamic equilibrium impact (on welfare, wages and labor allocation) of trade shocks and technological changes. The approach used in this paper follows the method developed in Artuç, Chaudhuri and McLaren (2010). Our estimates show that Argentinian workers face high average intersectoral adjustment costs. This result suggests that the adjustment of the labor market in response to shocks is slow.

本論文包括三篇有關「勞動力調整機制」及「失業」相關課題之研究。 這三篇研究分別在國際貿易理論的領域中，建立三個不同的理論分析架構與模型，進行討論有關勞動力調整的主題，整個論文的主軸及行文順序如下： 第一篇文章為「農村失業模型的理論與應用： WTO架構下的農業政策」，主要建構一個可能存在失業的理論模型。主要根據 Adam Smith 「剩餘生產力的出路」(vent for surplus)的理念下，本文主要針對在農村經濟出現生產要素「失業」的情況下，從剩餘生產力出路的觀點，將鄉村的過多勞動力或閒置土地，找到一個新的出口，再創造生產要素的價值。 第二篇文章為「勞動力調整機制與都市勞動力回流」，都市人口回流鄉村(return migration)為人口遷移的實證文獻所肯定的普遍現象，本文提供一個闡釋上述人口回流現象的理論基礎，討論勞動力的過度反應與都市人口回流(return migration)的形成。當鄉村地區勞動力過度外移至就業，一窩蜂跑到都市後反而成為都市中的失業人口，最後再選擇回流鄉村的動態行為模式。 最後，第三篇文章為「職前訓練與勞動力調整機制」，結合實質景氣循環模型中內生的勞動供給與跨部門的調整成本 (adjustment costs)的動態分析架構，從勞動者可以自己選擇要投入工作賺取報酬，或是不工作的決定，亦即，勞動者衡量「休閒」與「工作」所帶來的效用差異，決定投入生產的勞動供給量。同時，也考量到勞動市場的內部移動會造成資源配置的調整成本，因此，我們考慮勞動力跨部門移動需要經過職業訓練(training)的過程，才可正式生產。準此，在「內生的勞動供給」模型中納入「職業訓練」調整成本之後，能夠進一步釐清勞動市場內部的調整機制與其配置。