Diese Dissertation umfasst vier Aufsätze welche die Effekte von nicht-zufälliger Selektion betrachten. Im ersten Aufsatz wird analysiert welche Rolle die geänderte Zusammensetzung der Erwerbsbevölkerung für die Entwicklung der Lohnungleichheit spielt. Vollzeit-Erwerbstätige weisen zunehmend Episoden von Teilzeitarbeit und Erwerbsunterbrechungen in ihren Biographien auf. Dies hat maßgeblich zum Anstieg der Lohnungleichheit beigetragen. Der zweite Aufsatz betrachtet die Effekte von gesunkener Arbeitslosigkeit auf Lohnungleichheit.. Wenn sich die Selektion in Vollzeit oder Arbeitslosigkeit ändert, kann dies zu steigender Lohnungleichheit führen. Dies ist insbesondere dann der Fall wenn Personen neu in Beschäftigung kommen, die eine Negativauswahl der Erwerbsbevölkerung sind. Jedoch zeigt sich, als Resultat einer Analyse mit selektionskorrigierten Quantilsregressionen, dass diese veränderte Selektion nicht zum Anstieg der Lohnungleichheit beigetragen hat. Im dritten Aufsatz geht es um nicht-monotone Selektion bei Regression Discontinuity Designs (RDD). Die Annahmen, auf welchen RDDs beruhen, können verletzt sein wenn sich sowohl Individuen in die Maßnahmengruppe hinein, als auch aus ihr heraus selektieren. Der Aufsatz beschreibt diesen Selektionsmechanismus und zeigt seine praktische Relevanz. Zudem wird ein Spezifikationstest vorgestellt um das Problem im Vorfeld der Analyse zu erkennen. Der vierte Aufsatz untersucht Wählerpräferenzen für das Geschlecht politischer Kandidaten. Es wird analysiert ob das Zusammenspiel von Berufsinformationen und Geschlecht die geringere Repräsentation von Frauen erklären kann. Dazu wurde ein Feldexperiment durchgeführt. Es zeigt sich dass weibliche Kandidaten einen Stimmvorteil genießen solange keine Berufsinformationen angegeben sind. Sobald jedoch die Berufe der Kandidaten bekannt sind kehrt sich dies in einen Stimmvorteil für männliche Kandidaten um. / This thesis comprises four essays which study effects of non-random selection. The first essay analyzes the role of changes in labor force composition for the development of wage inequality among full-time workers. Of particular interest are the effects of increasingly common episodes of temporary part-time work and nonemployment among full-time workers. Such episodes, have contributed substantially to the rise in wage inequality. The second essay studies the effects of declining unemployment on inequality of wages. Changing selection over time between unemployment and full-time work could lead to increasingly diverse wages, particularly if sinking unemployment implies an influx of negatively selected workers into employment. However, results from a selection corrected quantile regression approach show that changing selection with respect to unobservables is not a contributor to the rise in wage inequality. The third essay studies non-monotonic selection in regression discontinuity designs (RDD). When similar numbers of individual select into and out of treatment simultaneously, the identifying assumption of the RDD can be violated. The essay describes the selection mechanisms and demonstrates it’s practical relevance. It then suggests an enhancement to the standard specification tests for RDDs, which can detect non-monotonic sorting in advance. The fourth essay studies voter’s valuation of candidate gender. It examines whether the presence of profession information coupled with voter preferences for stereotypical male occupations may explain part of the gender gap in parliaments. The analysis is conducted as a field experiment built into an exit-poll of voters in Germany in 2014. The results show a vote share bonus for women in the absence of profession information. Once voters know the profession of candidates, however, this changes towards a small edge for male candidates.

本文內容包含三個主題相近的議題，首先我們探討在貿易互動的情況下，國際能源價格衝擊所帶來的跨國衝擊效果，接著根據多個年度的資料，延用第一個議題的模型分析跨國衝掔效果的演變，以及這樣的演變與貿易趨勢之間的關係，最後則探討委外代工的貿易活動對經濟體系勞動市場的影響，企圖尋找台灣近年工資不均度逐漸下降的原因。 由第一個議題的分析結果可以發現，若要有效降低原物料價格上漲所帶來的衝擊，可從國內高耗能的產業 (如石油煉製品業) 著手，藉由技術移轉、跨國產業合作或研發投入等方式提升耗能產業的技術，改善生產結構；此外，藉由分散進口來源，可以有效降低進口拉動的物價上漲；最後，在國際能源價格上漲時，公用事業部門的價格管制，可以有效控制物價上漲，尤其對於天然資源缺乏的國家效果較為顯著，且愈多國家採行價格管制策略時，對降低物價衝擊的效果愈好。。 由第二個議題的分析可得知，各國的個別產業在三個不同的年度受到相同衝擊時，當產業的中間投入裡，能源及石油煉製品的占比愈高，則價格衝擊反應便愈大，這樣的影響效果主要反應了直接效果。若仔細檢視國內的各產業委外代工活動對價格衝擊效果的影響，則可以發現在產業別資料時，兩者間的關係並不明顯，但若將分析層級提高到整體國家的話，便可以發現委外代工比例或是國際專業分工程度愈高的國家，其受到的物價衝擊似乎稍微較低，而此一部份則是反應了跨國貿易傳遞效果。 最後，由第三個分析議題可以發現，台灣過去25年來技能與非技能勞工的工資差距逐漸拉近，這樣的趨勢與近年文獻所觀察的結果有明顯的不同，仔細檢視其中的端倪，我們可以發現台灣工資不均度雖然與相對勞動雇用仍為正相關，但工資不均度卻受到委外代工與對外直接投資負向的影響，其中，僅電子電機及機械類別的委外代工對工資不均度具有影響顯著，但民生工業及重工業類別卻不顯著，這樣的結果與近年台灣電子業發展的模式有關，雖然此產業委外生產比例日益攀升，但隨著台灣電子業在全球舉足輕重的地位，產值逐年大幅成長，雖然其中零組件愈來愈多仰賴委由開發中國家生產，但於台灣進行組裝仍需大量非技能勞工，因此委外生產將使工資不均度的情形減緩。另外，從資料中也發現，近年台灣日益減緩的工資不均度情形，主要是由於相對勞動供給的增量大於相對勞動需求所致。 / This thesis contents three approximate subjects for discussion. First of all, we confer the interaction of trades when the rise of international raw material price influences multinational; according to the data taken from many years, we employed the model of the first subject to analyze the development of inter-regional impact, its effect and also the relationship between the development and the trade tendency. Lastly, the influence of outsourcing towards the labor market in the economy will be discussed, in order to search for the reason, which is responsible for the chronicle decrease of wage inequality. The result of the first discussion shows us, to slow down the price impact which is caused by the rise of the raw material, we can undertake national companies with high energy consumption industries (e.g. petrochemical industry); on these excuses: Technique shifting, international industrial cooperation or investment of researches and so on, the technology of high energy consuming industries could be promoted to improve the production structure. Further than that, dispersing import resources could efficiently reduce the price increase caused by import. The price control at public utility could bridle price rise effectively, when international energy price is arising. This is especially obvious in countries with lack of natural resource, not forget to mention the more nations introduce price control tactic, the better it is to reduce the price impact. By the analysis of the second discussion, it is said when each country in each industry at three different years experienced the same impact, the higher the industrial’s usage of energy and petro-products for intermediate inputs, the strong is the reaction of price impact and this influence mainly responded to the direct effect. If we examine the relationship between price impact and proportion of outsourcing, we could notice that the relationship is not very conspicuous in industrial level data. But if we move the analyze level higher to the whole nation, we could discover that the higher the percentage of outsourcing is, the lower is the resulted price impact. And this is because of the transmission effect of the international trade. Last but not least, the third discussion let us know, that in the past 25 years in Taiwan, the wage inequality of high skill and low skill labor was reducing chronically. Such a trend is clearly different from the result which is shown in the recently studies. Even the wage inequality is positive proportioned with the relative labor employed, but it has been negatively influenced by outsourcing and outward direct investments. The negative relationship counts to the most outstanding in electronics and electrical machinery industries, but civil industry and heavy metal industry is not much remarkable. This result is related to the expand model of Taiwan in the recent years. Although, the percentage of outsourcing grows day by day, but with the importance of Taiwan’s electronics industry, the production arises substantially annually, even though more and more of its components is sourcing from development countries, but we still need many non-skilled personnel to fabricate those in Taiwan. That’s why outsourcing will decrease the wage inequality. Further than that, the recent wage inequality decrease in Taiwan is mainly effected by the surplus of relative labor supply.

La presente tesi raggruppa tre contributi che analizzano la partecipazione dei minori ad attività lavorative e scolastiche in Marocco, le variabili correlate con il benessere individuale e le differenze nei livelli salariali in Albania. I tre saggi tentano di fornire analisi empiriche basate sulla letteratura più recente e di contribuire allo sviluppo della metodologia quantitativa più comunemente utilizzata. / The present thesis is a collection of three contributions which investigate children’s schooling and labour participation in Morocco, the correlates of subjective well being and the differences in wage levels in Albania. The papers try to carry out empirical analyses of these issues based on the most recent developments in the relevant literature and to contribute to the empirical methodology commonly used.