Three Essays on the Formation and Impact of Economic Policy

Introduction In my thesis I argue that economic policy is all about economics and politics. Consequently, analysing and understanding economic policy ideally has at least two parts. The economics part, which is centered around the expected impact of a specific policy on the real economy both in terms of efficiency and equity. The insights of this part point into which direction the fine-tuning of economic policies should go. However, fine-tuning of economic policies will be most likely subject to political constraints. That is why, in the politics part, a much better understanding can be gained by taking into account how the incentives of politicians and special interest groups as well as the role played by different institutional features affect the formation of economic policies. The first part and chapter of my thesis concentrates on the efficiency-related impact of economic policies: how does corporate income taxation in general, and corporate income tax progressivity in specific, affect the creation of new firms? Reduced progressivity and flat-rate taxes are in vogue. By 2009, 22 countries are operating flat-rate income tax systems, as do 7 US states and 14 Swiss cantons (for corporate income only). Tax reform proposals in the spirit of the "flat tax" model typically aim to reduce three parameters: the average tax burden, the progressivity of the tax schedule, and the complexity of the tax code. In joint work, Marius Brülhart and I explore the implications of changes in these three parameters on entrepreneurial activity, measured by counts of firm births in a panel of Swiss municipalities. Our results show that lower average tax rates and reduced complexity of the tax code promote firm births. Controlling for these effects, reduced progressivity inhibits firm births. Our reading of these results is that tax progressivity has an insurance effect that facilitates entrepreneurial risk taking. The positive effects of lower tax levels and reduced complexity are estimated to be significantly stronger than the negative effect of reduced progressivity. To the extent that firm births reflect desirable entrepreneurial dynamism, it is not the flattening of tax schedules that is key to successful tax reforms, but the lowering of average tax burdens and the simplification of tax codes. Flatness per se is of secondary importance and even appears to be detrimental to firm births. The second part of my thesis, which corresponds to the second and third chapter, concentrates on how economic policies are formed. By the nature of the analysis, these two chapters draw on a broader literature than the first chapter. Both economists and political scientists have done extensive research on how economic policies are formed. Thereby, researchers in both disciplines have recognised the importance of special interest groups trying to influence policy-making through various channels. In general, economists base their analysis on a formal and microeconomically founded approach, while abstracting from institutional details. In contrast, political scientists' frameworks are generally richer in terms of institutional features but lack the theoretical rigour of economists' approaches. I start from the economist's point of view. However, I try to borrow as much as possible from the findings of political science to gain a better understanding of how economic policies are formed in reality. In the second chapter, I take a theoretical approach and focus on the institutional policy framework to explore how interactions between different political institutions affect the outcome of trade policy in presence of special interest groups' lobbying. Standard political economy theory treats the government as a single institutional actor which sets tariffs by trading off social welfare against contributions from special interest groups seeking industry-specific protection from imports. However, these models lack important (institutional) features of reality. That is why, in my model, I split up the government into a legislative and executive branch which can both be lobbied by special interest groups. Furthermore, the legislative has the option to delegate its trade policy authority to the executive. I allow the executive to compensate the legislative in exchange for delegation. Despite ample anecdotal evidence, bargaining over delegation of trade policy authority has not yet been formally modelled in the literature. I show that delegation has an impact on policy formation in that it leads to lower equilibrium tariffs compared to a standard model without delegation. I also show that delegation will only take place if the lobby is not strong enough to prevent it. Furthermore, the option to delegate increases the bargaining power of the legislative at the expense of the lobbies. Therefore, the findings of this model can shed a light on why the U.S. Congress often practices delegation to the executive. In the final chapter of my thesis, my coauthor, Antonio Fidalgo, and I take a narrower approach and focus on the individual politician level of policy-making to explore how connections to private firms and networks within parliament affect individual politicians' decision-making. Theories in the spirit of the model of the second chapter show how campaign contributions from lobbies to politicians can influence economic policies. There exists an abundant empirical literature that analyses ties between firms and politicians based on campaign contributions. However, the evidence on the impact of campaign contributions is mixed, at best. In our paper, we analyse an alternative channel of influence in the shape of personal connections between politicians and firms through board membership. We identify a direct effect of board membership on individual politicians' voting behaviour and an indirect leverage effect when politicians with board connections influence non-connected peers. We assess the importance of these two effects using a vote in the Swiss parliament on a government bailout of the national airline, Swissair, in 2001, which serves as a natural experiment. We find that both the direct effect of connections to firms and the indirect leverage effect had a strong and positive impact on the probability that a politician supported the government bailout.

Transcriptional activation of the utrophin promoter B by a constitutively active Ets-transcription factor.

Duchenne muscular dystrophy is an X-linked genetic disease caused by the absence of functional dystrophin. Pharmacological upregulation of utrophin, the autosomal homologue of dystrophin, offers a potential therapeutic approach to treat Duchenne patients. Full-length utrophin mRNA is transcribed from two alternative promoters, called A and B. In contrast to the utrophin promoter A, little is known about the factors regulating the activity of the utrophin promoter B. Computer analysis of this second promoter revealed the presence of several conserved binding motives for Ets-transcription factors. Using electrotransfer of cDNA into mouse muscles, we demonstrate that a genetically modified beta-subunit of the Ets-transcription factor GA-binding protein potently activates a utrophin promoter B reporter construct in innervated muscle fibers in vivo. These results make the GA-binding protein and the signaling cascade regulating its activity in muscle cells, potential targets for the pharmacological modulation of utrophin expression in Duchenne patients.

Gender-role alternation in the simultaneously hermaphroditic freshwater snail Physa acuta: not with the same partner

In simultaneous hermaphrodites, gender conflicts that arise from two potential mates sharing the same gender preference may be solved through conditional reciprocity (or gamete trading). Conditional reciprocity had initially been considered widespread, but recent studies suggest that its real occurrence may have been overestimated, possibly because most mating observations have been performed on isolated pairs of individuals. Some resulting patterns (e. g., non-random alternation of sexual roles) were indeed compatible with conditional reciprocity but could also have stemmed from the two partners independently executing their own mating strategy and being experimentally enforced to do so with the same partner. Non-random alternation of gender roles was recently documented in the simultaneously hermaphroditic freshwater snail Physa acuta. To distinguish between conditional and unconditional gender alternations, we observed copulations of individually marked snails reared at three contrasted densities. We showed that density affected the overall frequency of copulations during the first 2 days of the experiment with high-density boxes showing more copulations than low density boxes, but it did not affect gender alternation patterns. A change in gender role was observed more often than expected by chance over two successive copulations by the same individual, confirming previous studies. However, gender switches did not preferentially occur with the same partner. We conclude that gender alternation is not due to conditional reciprocity in P. acuta. It may rather stem from each individual having a preference for gender alternation. We finally discuss the mechanisms and the potential extent of this unconditional reciprocity.

When Cooperation Stumbles: the effects of grades on indicators of cooperation

(English Abstract) In western societies, grades are to date the most widespread means by which achievement and performance are assessed in educational contexts. Grades are used for their capacity to provide individuals with a clear indicator of success or failure, in particular in comparison to others; in this respect, we study their impact on particular work contexts requiring cooperation. Indeed, students are often exhorted to cooperate and work in groups, while at the same time assessed with grades and focused on inter-individual comparison. However, to the best of our knowledge, no work has investigated the effects of grades on cooperation and on indicators of cooperation, a central question to be addressed given its significance for educational trends encouraging cooperative practices, and which we propose to explore in the experimental parts of this thesis. The first experimental chapter, Chapter 4, investigates the effect of grades with regards to their capacity to highlight individual visibility and at the same time social comparison. It tries to disentangle which of these facets could affect a motivated bias likely to reduce cooperation, namely individuals' preference for information confirming their own choice. In two experiments, results showed that a graded-cooperative situation increased this preference effect in comparison to other conditions where only individual visibility was manipulated, and furthermore increased individuals' perception of a competitive atmosphere. Chapter 5 investigates the effect of grades on direct cooperative inter- individual interactions, namely on group information sharing. Two experiments showed that grades hindered informational communication between individuals, leading them to withhold crucial task-information. Finally, Chapter 6 investigates the effects of grades on another indicator of group cooperation, namely inter-individual coordination. Results indicated that showcasing grades at the onset of a cooperative task necessitating inter-individual coordination decreased group performance and elicited more negative dominant behaviours amongst participants. Together these results provide evidence that grades hamper group cooperation. We conclude by discussing implications for the practice of grading in Education. ------------------------------------------------------- (Résumé en langue française) Dans la plupart des pays occidentaux, les notes sont majoritairement utilisées pour évaluer la performance et rendre compte de la réussite scolaire des individus. Dans cette perspective, elles sont non seulement un indicateur de succès ou d'échec, mais aussi de la valeur comparative des individus. Dans cette thèse nous proposons de tester l'effet des notes lorsque celles-ci sont utilisées dans des contextes bien spécifiques de coopération. En effet, si les notes et la comparaison sociale sont pratique courante, les étudiants sont souvent encouragés et amenés à coopérer en groupe. Cependant, à notre connaissance, point d'études ont testé l'effet des notes sur la coopération; études qui seraient pourtant légitimes étant donné la tendance existante en milieu éducatif à encourager les pratiques coopératives. C'est précisément ce que proposent de faire les chapitres expérimentaux de cette thèse. Le premier (Chapitre 4) teste l'effet des notes au regard de leur capacité à accentuer à la fois la visibilité et la comparaison sociale. Deux expériences investiguent l'effet des notes et tentent de démêler ce qui, de la visibilité individuelle, de la comparaison sociale ou des deux, pourrait affecter un biais motivationnel qui réduit la propension à coopérer: la propension à préférer les informations qui confirment les choix de l'individu. Les résultats montrent qu'en situation coopérative, les notes accroissent ce biais comparativement à des situations où seule la visibilité individuelle est soulignée, suggérant de plus que les notes produisent une focalisation des individus sur une comparaison sociale compétitive. Le second (Chapitre 5) teste l'effet des notes sur les interactions coopératives des individus, précisément sur le partage d'information. Deux expériences montrent que dans un contexte de travail en groupe coopératif, les notes entravent le bon partage des informations entre individus, les amenant à faire de la rétention d'information. Enfin, le troisième (Chapitre 6) investigue l'effet des notes sur un autre indicateur de coopération en groupe: la coordination interindividuelle. Les résultats montrent que les notes réduisent la coordination des individus et les mènent à avoir des comportements de dominance négative entre eux. En somme, les notes entravent la coopération et réduisent les comportements coopératifs entre individus. Enfin, nous discutons des implications pour le milieu éducatif.

Latitudinal patterns in plant defense: evolution of cardenolides, their toxicity and induction following herbivory.

Attempts over the past 50 years to explain variation in the abundance, distribution and diversity of plant secondary compounds gave rise to theories of plant defense. Remarkably, few phylogenetically robust tests of these long-standing theories have been conducted. Using >50 species of milkweed (Asclepias spp.), we show that variation among plant species in the induction of toxic cardenolides is explained by latitude, with higher inducibility evolving more frequently at lower latitudes. We also found that: (1) the production of cardenolides showed positive-correlated evolution with the diversity of cardenolides, (2) greater cardenolide investment by a species is accompanied by an increase in an estimate of toxicity (measured as chemical polarity) and (3) instead of trading off, constitutive and induced cardenolides were positively correlated. Analyses of root and shoot cardenolides showed concordant patterns. Thus, milkweed species from lower latitudes are better defended with higher inducibility, greater diversity and added toxicity of cardenolides.

Wolves in sheep's clothing: SDO asymmetrically predicts perceived ethnic victimization among White and Latino students across three years

Dominant groups have claimed to be the targets of discrimination on several historical occasions during violent intergroup conflict and genocide.The authors argue that perceptions of ethnic victimization among members of dominant groups express social dominance motives and thus may be recruited for the enforcement of group hierarchy. They examine the antecedents of perceived ethnic victimization among dominants, following 561 college students over 3 years from freshman year to graduation year. Using longitudinal, cross-lagged structural equation modeling, the authors show that social dominance orientation (SDO) positively predicts perceived ethnic victimization among Whites but not among Latinos, whereas victimization does not predict SDO over time. In contrast, ethnic identity and victimization reciprocally predicted each other longitudinally with equal strength among White and Latino students. SDO is not merely a reflection of contextualized social identity concerns but a psychological, relational motivation that undergirds intergroup attitudes across extended periods of time and interacts with the context of group dominance.

Comparative genomics of ParaHox clusters of teleost fishes: gene cluster breakup and the retention of gene sets following whole genome duplications.

BACKGROUND: The evolutionary lineage leading to the teleost fish underwent a whole genome duplication termed FSGD or 3R in addition to two prior genome duplications that took place earlier during vertebrate evolution (termed 1R and 2R). Resulting from the FSGD, additional copies of genes are present in fish, compared to tetrapods whose lineage did not experience the 3R genome duplication. Interestingly, we find that ParaHox genes do not differ in number in extant teleost fishes despite their additional genome duplication from the genomic situation in mammals, but they are distributed over twice as many paralogous regions in fish genomes. RESULTS: We determined the DNA sequence of the entire ParaHox C1 paralogon in the East African cichlid fish Astatotilapia burtoni, and compared it to orthologous regions in other vertebrate genomes as well as to the paralogous vertebrate ParaHox D paralogons. Evolutionary relationships among genes from these four chromosomal regions were studied with several phylogenetic algorithms. We provide evidence that the genes of the ParaHox C paralogous cluster are duplicated in teleosts, just as it had been shown previously for the D paralogon genes. Overall, however, synteny and cluster integrity seems to be less conserved in ParaHox gene clusters than in Hox gene clusters. Comparative analyses of non-coding sequences uncovered conserved, possibly co-regulatory elements, which are likely to contain promoter motives of the genes belonging to the ParaHox paralogons. CONCLUSION: There seems to be strong stabilizing selection for gene order as well as gene orientation in the ParaHox C paralogon, since with a few exceptions, only the lengths of the introns and intergenic regions differ between the distantly related species examined. The high degree of evolutionary conservation of this gene cluster's architecture in particular - but possibly clusters of genes more generally - might be linked to the presence of promoter, enhancer or inhibitor motifs that serve to regulate more than just one gene. Therefore, deletions, inversions or relocations of individual genes could destroy the regulation of the clustered genes in this region. The existence of such a regulation network might explain the evolutionary conservation of gene order and orientation over the course of hundreds of millions of years of vertebrate evolution. Another possible explanation for the highly conserved gene order might be the existence of a regulator not located immediately next to its corresponding gene but further away since a relocation or inversion would possibly interrupt this interaction. Different ParaHox clusters were found to have experienced differential gene loss in teleosts. Yet the complete set of these homeobox genes was maintained, albeit distributed over almost twice the number of chromosomes. Selection due to dosage effects and/or stoichiometric disturbance might act more strongly to maintain a modal number of homeobox genes (and possibly transcription factors more generally) per genome, yet permit the accumulation of other (non regulatory) genes associated with these homeobox gene clusters.

Bridging the Gap: establishing the necessary infrastructure and knowledge for teaching and research in neuroscience in Africa.

Advances in neuroscience research over the last few decades have increased our understanding of how individual neurons acquire their specific properties and assemble into complex circuits, and how these circuits are affected in disease. One of the important motives driving neuroscience research is the development of new scientific techniques and interdisciplinary cooperation. Compared to developed countries, many countries on the African continent are confronted with poor facilities, lack of funding or career development programs for neuroscientists, all of which deter young scientists from taking up neuroscience as a career choice. This article highlights some steps that are being taken to promote neuroscience education and research in Africa.

Education, Equity and Distributive Beliefs: Evidences from the Chilean Case

During the year 2011, Chile has been scenario of several student's demonstrations claiming for more equity in the access to the higher education. The high support to the protests by the side of the general population (nearly 89% of approval in public opinion polls) seems to suggest the existence of a large consensus about the weaknesses of the Chilean educative model, a model that would challenge the traditional ideals of meritocracy and social mobility that are at the core of the educational systems in modern societies. In this context, a question that remains open is to what extent these claims are mostly based on consensual equality ideals, or whether they are influenced by individual socio-economic determinants vis-à-vis rational motives. Using data of the social inequality module International Social Survey Program (ISSP) of 2009, this research analyzes perceptions and beliefs about education and the distributive system as well as the influence of income and educational variables, through a structural equation modeling framework. Preliminary results indicate the presence of socioeconomic cleavages in relation to the fairness of the educational system, questioning the assumption about a normative consensus.

Being Drunk to Have Fun or to Forget Problems? Identifying Enhancement and Coping Drinkers Among Risky Drinking Adolescents

Prevention programs in adolescence are particularly effective if they target homogeneous risk groups of adolescents who share a combination of particular needs and problems. The present work aims to identify and classify risky single-occasion drinking (RSOD) adolescents according to their motivation to engage in drinking. An easy-to-use coding procedure was developed. It was validated by means of cluster analyses and structural equation modeling based on two randomly selected subsamples of a nationally representative sample of 2,449 12- to 18-year-old RSOD students in Switzerland. Results revealed that the coding procedure classified RSOD adolescents as either enhancement drinkers or coping drinkers. The high concordance (Sample A: kappa - .88, Sample B: kappa - .90) with the results of the cluster analyses demonstrated the convergent validity of the coding classification. The fact that enhancement drinkers in both subsamples were found to go out more frequently in the evenings and to have more satisfactory social relationships, as well as a higher proportion of drinking peers and a lower likelihood to drink at home than coping drinkers demonstrates the concurrent validity of the classification. To conclude, the coding procedure appears to be a valid, reliable, and easy-to-use tool that can help better adapt prevention activities to adolescent risky drinking motives.

Medical and legal professionals' attitudes towards confidentiality and disclosure of clinical information in forensic settings: a survey using case vignettes.

OBJECTIVE: When potentially dangerous patients reveal criminal fantasies to their therapists, the latter must decide whether this information has to be transmitted to a third person in order to protect potential victims. We were interested in how medical and legal professionals handle such situations in the context of prison medicine and forensic evaluations. We aimed to explore the motives behind their actions and to compare these professional groups. METHOD: A mail survey was conducted among medical and legal professionals using five fictitious case vignettes. For each vignette, participants were asked to answer questions exploring what the professional should do in the situation and to explain their justification for the chosen response. RESULTS: A total of 147 questionnaires were analysed. Agreement between participants varied from one scenario to another. Overall, legal professionals tended to disclose information to a third party more easily than medical professionals, the latter tending to privilege confidentiality and patient autonomy over security. Perception of potential danger in a given situation was not consistently associated with actions. CONCLUSION: Professionals' opinions and attitudes regarding the confidentiality of potentially dangerous patients differ widely and appear to be subjectively determined. Shared discussions about clinical situations could enhance knowledge and competencies and reduce differences between professional groups.

Rules of origin : from analysis to reform

General Introduction This thesis can be divided into two main parts :the first one, corresponding to the first three chapters, studies Rules of Origin (RoOs) in Preferential Trade Agreements (PTAs); the second part -the fourth chapter- is concerned with Anti-Dumping (AD) measures. Despite wide-ranging preferential access granted to developing countries by industrial ones under North-South Trade Agreements -whether reciprocal, like the Europe Agreements (EAs) or NAFTA, or not, such as the GSP, AGOA, or EBA-, it has been claimed that the benefits from improved market access keep falling short of the full potential benefits. RoOs are largely regarded as a primary cause of the under-utilization of improved market access of PTAs. RoOs are the rules that determine the eligibility of goods to preferential treatment. Their economic justification is to prevent trade deflection, i.e. to prevent non-preferred exporters from using the tariff preferences. However, they are complex, cost raising and cumbersome, and can be manipulated by organised special interest groups. As a result, RoOs can restrain trade beyond what it is needed to prevent trade deflection and hence restrict market access in a statistically significant and quantitatively large proportion. Part l In order to further our understanding of the effects of RoOs in PTAs, the first chapter, written with Pr. Olivier Cadot, Celine Carrère and Pr. Jaime de Melo, describes and evaluates the RoOs governing EU and US PTAs. It draws on utilization-rate data for Mexican exports to the US in 2001 and on similar data for ACP exports to the EU in 2002. The paper makes two contributions. First, we construct an R-index of restrictiveness of RoOs along the lines first proposed by Estevadeordal (2000) for NAFTA, modifying it and extending it for the EU's single-list (SL). This synthetic R-index is then used to compare Roos under NAFTA and PANEURO. The two main findings of the chapter are as follows. First, it shows, in the case of PANEURO, that the R-index is useful to summarize how countries are differently affected by the same set of RoOs because of their different export baskets to the EU. Second, it is shown that the Rindex is a relatively reliable statistic in the sense that, subject to caveats, after controlling for the extent of tariff preference at the tariff-line level, it accounts for differences in utilization rates at the tariff line level. Finally, together with utilization rates, the index can be used to estimate total compliance costs of RoOs. The second chapter proposes a reform of preferential Roos with the aim of making them more transparent and less discriminatory. Such a reform would make preferential blocs more "cross-compatible" and would therefore facilitate cumulation. It would also contribute to move regionalism toward more openness and hence to make it more compatible with the multilateral trading system. It focuses on NAFTA, one of the most restrictive FTAs (see Estevadeordal and Suominen 2006), and proposes a way forward that is close in spirit to what the EU Commission is considering for the PANEURO system. In a nutshell, the idea is to replace the current array of RoOs by a single instrument- Maximum Foreign Content (MFC). An MFC is a conceptually clear and transparent instrument, like a tariff. Therefore changing all instruments into an MFC would bring improved transparency pretty much like the "tariffication" of NTBs. The methodology for this exercise is as follows: In step 1, I estimate the relationship between utilization rates, tariff preferences and RoOs. In step 2, I retrieve the estimates and invert the relationship to get a simulated MFC that gives, line by line, the same utilization rate as the old array of Roos. In step 3, I calculate the trade-weighted average of the simulated MFC across all lines to get an overall equivalent of the current system and explore the possibility of setting this unique instrument at a uniform rate across lines. This would have two advantages. First, like a uniform tariff, a uniform MFC would make it difficult for lobbies to manipulate the instrument at the margin. This argument is standard in the political-economy literature and has been used time and again in support of reductions in the variance of tariffs (together with standard welfare considerations). Second, uniformity across lines is the only way to eliminate the indirect source of discrimination alluded to earlier. Only if two countries face uniform RoOs and tariff preference will they face uniform incentives irrespective of their initial export structure. The result of this exercise is striking: the average simulated MFC is 25% of good value, a very low (i.e. restrictive) level, confirming Estevadeordal and Suominen's critical assessment of NAFTA's RoOs. Adopting a uniform MFC would imply a relaxation from the benchmark level for sectors like chemicals or textiles & apparel, and a stiffening for wood products, papers and base metals. Overall, however, the changes are not drastic, suggesting perhaps only moderate resistance to change from special interests. The third chapter of the thesis considers whether Europe Agreements of the EU, with the current sets of RoOs, could be the potential model for future EU-centered PTAs. First, I have studied and coded at the six-digit level of the Harmonised System (HS) .both the old RoOs -used before 1997- and the "Single list" Roos -used since 1997. Second, using a Constant Elasticity Transformation function where CEEC exporters smoothly mix sales between the EU and the rest of the world by comparing producer prices on each market, I have estimated the trade effects of the EU RoOs. The estimates suggest that much of the market access conferred by the EAs -outside sensitive sectors- was undone by the cost-raising effects of RoOs. The chapter also contains an analysis of the evolution of the CEECs' trade with the EU from post-communism to accession. Part II The last chapter of the thesis is concerned with anti-dumping, another trade-policy instrument having the effect of reducing market access. In 1995, the Uruguay Round introduced in the Anti-Dumping Agreement (ADA) a mandatory "sunset-review" clause (Article 11.3 ADA) under which anti-dumping measures should be reviewed no later than five years from their imposition and terminated unless there was a serious risk of resumption of injurious dumping. The last chapter, written with Pr. Olivier Cadot and Pr. Jaime de Melo, uses a new database on Anti-Dumping (AD) measures worldwide to assess whether the sunset-review agreement had any effect. The question we address is whether the WTO Agreement succeeded in imposing the discipline of a five-year cycle on AD measures and, ultimately, in curbing their length. Two methods are used; count data analysis and survival analysis. First, using Poisson and Negative Binomial regressions, the count of AD measures' revocations is regressed on (inter alia) the count of "initiations" lagged five years. The analysis yields a coefficient on measures' initiations lagged five years that is larger and more precisely estimated after the agreement than before, suggesting some effect. However the coefficient estimate is nowhere near the value that would give a one-for-one relationship between initiations and revocations after five years. We also find that (i) if the agreement affected EU AD practices, the effect went the wrong way, the five-year cycle being quantitatively weaker after the agreement than before; (ii) the agreement had no visible effect on the United States except for aone-time peak in 2000, suggesting a mopping-up of old cases. Second, the survival analysis of AD measures around the world suggests a shortening of their expected lifetime after the agreement, and this shortening effect (a downward shift in the survival function postagreement) was larger and more significant for measures targeted at WTO members than for those targeted at non-members (for which WTO disciplines do not bind), suggesting that compliance was de jure. A difference-in-differences Cox regression confirms this diagnosis: controlling for the countries imposing the measures, for the investigated countries and for the products' sector, we find a larger increase in the hazard rate of AD measures covered by the Agreement than for other measures.

Guayule and Russian dandelion as alternative sources of natural rubber.

Natural rubber, obtained almost exclusively from the Para rubber tree (Hevea brasiliensis), is a unique biopolymer of strategic importance that, in many of its most significant applications, cannot be replaced by synthetic rubber alternatives. Several pressing motives lead to the search for alternative sources of natural rubber. These include increased evidence of allergenic reactions to Hevea rubber, the danger that the fungal pathogen Microcyclus ulei, causative agent of South American Leaf Blight (SALB), might spread to Southeast Asia, which would severely disrupt rubber production, potential shortages of supply due to increasing demand and changes in land use, and a general trend towards the replacement of petroleum-derived chemicals with renewables. Two plant species have received considerable attention as potential alternative sources of natural rubber: the Mexican shrub Guayule (Parthenium argentatum Gray) and the Russian dandelion (Taraxacum koksaghyz). This review will summarize the current production methods and applications of natural rubber (dry rubber and latex), the threats to the production of natural rubber from the rubber tree, and describe the current knowledge of the production of natural rubber from guayule and Russian dandelion.

Revising the Cannabis Use Disorders Identification Test (CUDIT) by means of Item Response Theory.

Cannabis use among adolescents and young adults has become a major public health challenge. Several European countries are currently developing short screening instruments to identify 'problematic' forms of cannabis use in general population surveys. One such instrument is the Cannabis Use Disorders Identification Test (CUDIT), a 10-item questionnaire based on the Alcohol Use Disorders Identification Test. Previous research found that some CUDIT items did not perform well psychometrically. In the interests of improving the psychometric properties of the CUDIT, this study replaces the poorly performing items with new items that specifically address cannabis use. Analyses are based on a sub-sample of 558 recent cannabis users from a representative population sample of 5722 individuals (aged 13-32) who were surveyed in the 2007 Swiss Cannabis Monitoring Study. Four new items were added to the original CUDIT. Psychometric properties of all 14 items, as well as the dimensionality of the supplemented CUDIT were then examined using Item Response Theory. Results indicate the unidimensionality of CUDIT and an improvement in its psychometric performance when three original items (usual hours being stoned; injuries; guilt) are replaced by new ones (motives for using cannabis; missing out leisure time activities; difficulties at work/school). However, improvements were limited to cannabis users with a high problem score. For epidemiological purposes, any further revision of CUDIT should therefore include a greater number of 'easier' items.

Three essays on liquidity risk

Preface In this thesis we study several questions related to transaction data measured at an individual level. The questions are addressed in three essays that will constitute this thesis. In the first essay we use tick-by-tick data to estimate non-parametrically the jump process of 37 big stocks traded on the Paris Stock Exchange, and of the CAC 40 index. We separate the total daily returns in three components (trading continuous, trading jump, and overnight), and we characterize each one of them. We estimate at the individual and index levels the contribution of each return component to the total daily variability. For the index, the contribution of jumps is smaller and it is compensated by the larger contribution of overnight returns. We test formally that individual stocks jump more frequently than the index, and that they do not respond independently to the arrive of news. Finally, we find that daily jumps are larger when their arrival rates are larger. At the contemporaneous level there is a strong negative correlation between the jump frequency and the trading activity measures. The second essay study the general properties of the trade- and volume-duration processes for two stocks traded on the Paris Stock Exchange. These two stocks correspond to a very illiquid stock and to a relatively liquid stock. We estimate a class of autoregressive gamma process with conditional distribution from the family of non-central gamma (up to a scale factor). This process was introduced by Gouriéroux and Jasiak and it is known as Autoregressive gamma process. We also evaluate the ability of the process to fit the data. For this purpose we use the Diebold, Gunther and Tay (1998) test; and the capacity of the model to reproduce the moments of the observed data, and the empirical serial correlation and the partial serial correlation functions. We establish that the model describes correctly the trade duration process of illiquid stocks, but have problems to adjust correctly the trade duration process of liquid stocks which present long-memory characteristics. When the model is adjusted to volume duration, it successfully fit the data. In the third essay we study the economic relevance of optimal liquidation strategies by calibrating a recent and realistic microstructure model with data from the Paris Stock Exchange. We distinguish the case of parameters which are constant through the day from time-varying ones. An optimization problem incorporating this realistic microstructure model is presented and solved. Our model endogenizes the number of trades required before the position is liquidated. A comparative static exercise demonstrates the realism of our model. We find that a sell decision taken in the morning will be liquidated by the early afternoon. If price impacts increase over the day, the liquidation will take place more rapidly.