Imperfect competition and market liquidity with a supply informed trader

We develop a model of insider trading where agents have private information either about liquidation value or about supply and behave strategically to maximize their profits. The supply informed trader plays a dual role in market making and in information revelation. This trader not only reveals a part of the information he owns, but he also induces the other traders to reveal more of their private information. The presence of different types of information decreases market liquidity and induces non-monotonicity of the market indicators with respect to the variance of liquidation value. Replacing the noise introduced by liquidity traders with a random supply also allows us to study the effect the shocks on different components of supply have on prices and quantities.

Environmental regulation: choice of instruments under imperfect compliance

Compliance is an important issue in environmental regulation. In this paper, we discuss some of the key elements of the problem and analyze a situation where emissions are not random and firms are risk-neutral. We study the firm's decision on emissions and compliance when the environmental regulation is based on standards and the enforcement agency audits the firm with a certain probability. We then compare total emissions when environmental regulation is based on different instruments: standards, taxes, and tradable permits. We show that when compliance is an issue, environmental taxes are superior to the other instruments. We also analyze the (static) efficiency of the solution.

Cooperative strategies for imperfect CSI scenarios based on distributed Alamouti

Les comunicacions cooperatives estan guanyant un gran interès en les comunicacions modernes degut a que permeten millorar la transmissió dʼinformació entre un emissor i un receptor utilitzant una sèrie de terminals situats entre ells. Aquest projecte és un estudi complet del sistemes cooperatius, analitzant el seu rendiment i comparant lʼús dʼun sol dʼaquests terminals amb lʼús del codi Alamouti, que utilitza dos terminals. Primer hi ha una introducció als sistemes cooperatius i a la teoria de la informació. Després hem estudiat un sistema cooperatiu amb la teoria de la informació com a base, en termes de probabilitat de fallada del sistema, i posteriorment lʼhem adaptat a un sistema cooperatiu real utilitzant una modulació QPSK, estudiant la seva probabilitat dʼerror de paquet. Finalment es proposen diversos protocols que permeten millorar el rendiment del sistema cooperatiu estudiat.

Intraovarian sperm storage in Helicolenus dactylopterus dactylopterus fertilitzation, crypt formation and maintenance of stored sperm

The females of the bluemouth rockfish, Helicolenus dactylopterus dactylopterus (DelaRoche, 1809), store sperm within their ovaries for periods of up to 10 months. Twenty six females with standard lengths between 152 and 257 mm and six males with standard lengths between 253 and 209 mm were caught storage crypts with stored spermatozoa and to describe their evolution over the year. After internal fertilization and once sperm reaches the ovary, a crypt forms probably by an epithelial inclusion at the base of the lamellae of one or several spermatozoa groups that are floating freely in the interlamellar space of the ovarian lumen. Stored spermatozoa have a large cytoplasm bag surrounding their heads. This bag could serve as a nutritive reservoir during the long storage period. Many desmosonal and tight junctions between the crypt cells ensure tha male sex cells are protected against the female immune system

Probabilistic models to assist maintenance of multiple instruments

The paper discusses maintenance challenges of organisations with a huge number of devices and proposes the use of probabilistic models to assist monitoring and maintenance planning. The proposal assumes connectivity of instruments to report relevant features for monitoring. Also, the existence of enough historical registers with diagnosed breakdowns is required to make probabilistic models reliable and useful for predictive maintenance strategies based on them. Regular Markov models based on estimated failure and repair rates are proposed to calculate the availability of the instruments and Dynamic Bayesian Networks are proposed to model cause-effect relationships to trigger predictive maintenance services based on the influence between observed features and previously documented diagnostics

Additional utility of insiders with imperfect dynamical information

In this paper we consider an insider with privileged information thatis affected by an independent noise vanishing as the revelation timeapproaches. At this time, information is available to every trader. Ourfinancial markets are based on Wiener space. In probabilistic terms weobtain an infinite dimensional extension of Jacod s theorem to covercases of progressive enlargement of filtrations. The application ofthis result gives the semimartingale decomposition of the originalWiener process under the progressively enlarged filtration. As anapplication we prove that if the rate at which the additional noise inthe insider s information vanishes is slow enough then there is noarbitrage and the additional utility of the insider is finite.

Income maintenance programs and multidimensional screening

This paper examines properties of optimal poverty assistance programs under different informational environments using an income maintenanceframework. To that end, we make both the income generating ability andthe disutility of labor of individuals unobservable, and compare theresulting benefit schedules with those of programs found in the UnitedStates since Welfare Reform (1996). We find that optimal programs closelyresemble a Negative Income Tax with a Benefit Reduction rate that dependson the distribution of population characteristics. A policy of workfare(unpaid public sector work) is inefficient when disutility of labor isunobservable, but minimum work requirements (for paid work) may be usedin that same environment. The distortions to work incentives and thepresence of minimum work requirements depend on the observability andrelative importance of the population's characteristics.

Firm investment in imperfect capital markets: A structural estimation

We set up a dynamic model of firm investment in which liquidity constraintsenter explicity into the firm's maximization problem. The optimal policyrules are incorporated into a maximum likelihood procedure which estimatesthe structural parameters of the model. Investment is positively related tothe firm's internal financial position when the firm is relatively poor. This relationship disappears for wealthy firms, which can reach theirdesired level of investment. Borrowing is an increasing function of financial position for poor firms. This relationship is reversed as a firm's financial position improves, and large firms hold little debt.Liquidity constrained firms may be unused credits lines and the capacity toinvest further if they desire. However the fear that liquidity constraintswill become binding in the future induces them to invest only when internalresources increase.We estimate the structural parameters of the model and use them to quantifythe importance of liquidity constraints on firms' investment. We find thatliquidity constraints matter significantly for the investment decisions of firms. If firms can finance investment by issuing fresh equity, rather than with internal funds or debt, average capital stock is almost 35% higher overa period of 20 years. Transitory shocks to internal funds have a sustained effect on the capital stock. This effect lasts for several periods and ismore persistent for small firms than for large firms. A 10% negative shock to firm fundamentals reduces the capital stock of firms which face liquidityconstraints by almost 8% over a period as opposed to only 3.5% for firms which do not face these constraints.

Parental altruism under imperfect information: Theory and evidence

Can we reconcile the predictions of the altruism model of the familywith the evidence on intervivos transfers in the US? This paper expandsthe altruism model by introducing e ?ort of the child and by relaxingthe assumption of perfect information of the parent about the labormarket opportunities of the child. First, I solve and simulate a modelof altruism under imperfect information. Second, I use cross-sectionaldata to test a prediction of the model: Are parental transfers especiallyresponsive to the income variations of children who are very attached tothe labor market? The results suggest that imperfect information accountsfor several patterns of intergenerational transfers in the US.

Increasing returns, imperfect competition and factor prices

We show how, in general equilibrium models featuring increasing returns, imperfectcompetition and endogenous markups, changes in the scale of economic activity affectincome distribution across factors. Whenever final goods are gross-substitutes (gross-complements), a scale expansion raises (lowers) the relative reward of the scarce factoror the factor used intensively in the sector characterized by a higher degree of product differentiation and higher fixed costs. Under very reasonable hypothesis, our theory suggests that scale is skill-biased. This result provides a microfoundation for the secular increase in the relative demand for skilled labor. Moreover, it constitutes an important link among major explanations for the rise in wage inequality: skill-biased technical change, capital-skill complementarities and international trade. We provide new evidence on the mechanism underlying the skill bias of scale.

Parental altruism under imperfect information: Theory and evidence

Can we reconcile the predictions of the altruism model of the family withthe evidence on parental monetary transfers in the US? This paper providesa new assessment of this question. I expand the altruism model by introducingeffort of the child and by relaxing the assumption of perfect informationof the parent about the labor market opportunities of the child. First,I solve and simulate a model of altruism and labor supply under imperfectinformation. Second, I use cross-sectional data to test the following prediction of the model: Are parental transfers especially responsive tothe income variations of children who are very attached to the labor market? The results of the analysis suggest that imperfect informationaccounts for many of the patterns of intergenerational transfers in theUS.

Maintenance of A/P body regions in planarians by TCEN49, a putative cystine-knot neurotrophin.

In freshwater planarians, the protein TCEN49 has been linked to the regional specification of the central body region, which includes the pharynx.

Effectiveness of psychotropic medications in the maintenance phase of bipolar disorder:a meta-analysis of randomized controlled trials

The purpose of this meta-analysis was to examine the efficacy of maintenance treatments for bipolar disorder. Placebo-controlled or active comparator bipolar maintenance clinical trials of ≥6 months' duration with at least 15 patients/treatment group were identified using Medline, EMBASE, clinicaltrials.gov, and Cochrane databases (1993 to July 2010). The main outcome measure was relative risk for relapse for patients in remission. Twenty trials (5,364 patients) were identified. Overall, lithium and quetiapine were the most studied agents (eight and five trials, respectively). The majority of studies included patients who had previously responded to treatment for an acute episode. All interventions, with the exception of perphenazine+mood stabilizer, showed a relative risk for manic/mixed or depressive relapse below 1.0, although there was variation in the statistical significance of the findings vs. placebo. No monotherapy was associated with a significantly reduced risk for both manic/mixed and depressed relapse. Of the combination treatments, only quetiapine+lithium/divalproex, was associated with a significantly reduced risk vs. comparator (placebo+lithium/valproate) for relapse at both the manic/mixed and depressed poles of bipolar illness. Limitations for the analysis include differences in study durations and definitions of relapse. In conclusion, available maintenance therapies show considerable variation in efficacy. The efficacy of lithium and divalproex has been confirmed, but newer therapies, such as a number of atypical antipsychotics were also shown to be effective in bipolar disorder. Efficacy of all maintenance interventions needs to be balanced against the safety and tolerability profiles of individual agents.

Robust power allocation algorithms for MIMO OFDM systems with imperfect CSI

This paper presents a Bayesian approach to the design of transmit prefiltering matrices in closed-loop schemes robust to channel estimation errors. The algorithms are derived for a multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system. Two different optimizationcriteria are analyzed: the minimization of the mean square error and the minimization of the bit error rate. In both cases, the transmitter design is based on the singular value decomposition (SVD) of the conditional mean of the channel response, given the channel estimate. The performance of the proposed algorithms is analyzed,and their relationship with existing algorithms is indicated. As withother previously proposed solutions, the minimum bit error rate algorithmconverges to the open-loop transmission scheme for very poor CSI estimates.

Traducció i adopció a l'Índia: Hindu Adoptions And Maintenance Act, 1956

L’objectiu principal d’aquest treball de fi de grau és fer-se càrrec d’una traducció jurídica amb tot el què això implica: documentar-se a través de fonts fiables, emprar les eines adequades, lliurar-lo dins el termini establert, entre d’altres. En aquest cas, és una traducció de les lleis que regulen les adopcions a l’Índia. A més, en aquest treball també s’explica breument el dret civil a Catalunya i es compara amb el de l’Índia, ja que es basen en idees molt diferents. Aquests tipus de traduccions exigeixen precisió i claredat perquè els conceptes i les estructures sintàctiques acostumen a ser molt complexes. A continuació, hi ha detallat cada pas que s’ha seguit per tal d’assolir l’objectiu principal.