Of Coalition and Speed: Passage and Duration of Statutes in Uruguay's Parliament, 1985-2000

We report preliminary findings from analysis of a database under construction. The paper explores the legislative process in search for some of the alleged consequences of cabinet coalitions in a presidential system. Coalition effects should be less evident in the success of executive initiatives: strategic behavior hampers this intuitive measure of performance. Better measures, because less subject to strategic considerations, are the odds of passage of legislators' bills and the time proposals take to be approved. Thus measured, coalition effects are discernible. Analysis of the universe of proposals processed in the fragmented Uruguayan Parliament between 1985 and 2000 reveals that coalition, observed about half the period, swells success rates of coalition members by 60% on average (and by as much as 150% for those close to the president). Event history analysis shows that coalitions cut the wait for an executive bill by 3 months, 1/6th the average wait. The reverse effect is felt on the duration of legislators' bills.

Dealing with Tyranny: International Sanctions and Autocrats’ Duration

This paper enquires into whether economic sanctions are effective in destabilizing authoritarian rulers. We argue that this effect is mediated by the type of authoritarian regime against which sanctions are imposed. Thus, personalist regimes and monarchies, which are more dependent on aid and resource rents to maintain their patronage networks, are more likely to be affected by sanctions. In contrast, single-party and military regimes are able to maintain (and even increase) their tax revenues and to reallocate their expenditures and so increase their levels of cooptation. Data on sanction episodes, authoritarian rulers and regimes covering the period 1946–2000 have allowed us to test our hypotheses. To do so, duration models have been run, and the results confirm that personalist autocrats are more vulnerable to foreign pressure. Concretely, the analysis of the modes of exit reveals that sanctions increase the likelihood of an irregular change of ruler, such as a coup. Sanctions are basically ineffective when targeting single-party or military regimes.

Towards an emotion-driven interactive music system: ridging the gaps between affect, physiology and sound generation

Report for the scientific sojourn at the Stanford University from January until June 2007. Music is well known for affecting human emotional states, yet the relationship between specific musical parameters and emotional responses is still not clear. With the advent of new human-computer interaction (HCI) technologies, it is now possible to derive emotion-related information from physiological data and use it as an input to interactive music systems. Providing such implicit musical HCI will be highly relevant for a number of applications including music therapy, diagnosis, nteractive gaming, and physiologically-based musical instruments. A key question in such physiology-based compositions is how sound synthesis parameters can be mapped to emotional states of valence and arousal. We used both verbal and heart rate responses to evaluate the affective power of five musical parameters. Our results show that a significant correlation exists between heart rate and the subjective evaluation of well-defined musical parameters. Brightness and loudness showed to be arousing parameters on subjective scale while harmonicity and even partial attenuation factor resulted in heart rate changes typically associated to valence. This demonstrates that a rational approach to designing emotion-driven music systems for our public installations and music therapy applications is possible.

Sound Texture Modelling

In the PhD thesis “Sound Texture Modeling” we deal with statistical modelling or textural sounds like water, wind, rain, etc. For synthesis and classification. Our initial model is based on a wavelet tree signal decomposition and the modeling of the resulting sequence by means of a parametric probabilistic model, that can be situated within the family of models trainable via expectation maximization (hidden Markov tree model ). Our model is able to capture key characteristics of the source textures (water, rain, fire, applause, crowd chatter ), and faithfully reproduces some of the sound classes. In terms of a more general taxonomy of natural events proposed by Graver, we worked on models for natural event classification and segmentation. While the event labels comprise physical interactions between materials that do not have textural propierties in their enterity, those segmentation models can help in identifying textural portions of an audio recording useful for analysis and resynthesis. Following our work on concatenative synthesis of musical instruments, we have developed a pattern-based synthesis system, that allows to sonically explore a database of units by means of their representation in a perceptual feature space. Concatenative syntyhesis with “molecules” built from sparse atomic representations also allows capture low-level correlations in perceptual audio features, while facilitating the manipulation of textural sounds based on their physical and perceptual properties. We have approached the problem of sound texture modelling for synthesis from different directions, namely a low-level signal-theoretic point of view through a wavelet transform, and a more high-level point of view driven by perceptual audio features in the concatenative synthesis setting. The developed framework provides unified approach to the high-quality resynthesis of natural texture sounds. Our research is embedded within the Metaverse 1 European project (2008-2011), where our models are contributting as low level building blocks within a semi-automated soundscape generation system.

Investment, duration, and exit strategies for corporate and independent venture capital-backed start-ups

We propose a model of investment, duration, and exit strategies for start-ups backed by venture capital (VC) funds that accounts for the high level of uncertainty, the asymmetry of information between insiders and outsiders, and the discount rate. Our analysis predicts that start-ups backed by corporate VC funds remain for a longer period of time before exiting and receive larger investment amounts than those financed by independent VC funds. Although a longer duration leads to a higher likelihood of an exit through an acquisition, a larger investment increases the probability of an IPO exit. These predictions find strong empirical support.

Does Warfare Matter? Severity, Duration, and Outcomes of Civil Wars

Importa si una guerra civil es combat com un conflicte irregular, convencional o simètric no convencional? En altres paraules, tenen les “tecnologies de la rebel·lió” un impacte sobre la gravetat d’una guerra, la seva durada o el seu resultat? Aquest treball mostra que els conflictes irregulars duren més que els altres tipus de conflicte, mentre els convencionals tendeixen a ser més greus en termes de letalitat al camp de batalla. D’altra banda, els conflictes irregulars tendeixen a ser guanyats pels governs, mentre els altres són més propensos a acabar en empat. Substancialment, aquests resultats ens ajuden a donar sentit a l’evolució de les guerres civils, les quals tendeixen a ser més curtes, més intenses i més difícils per als governs. Teòricament, aquests resultats donen suport a la importància de la tecnologia de rebel·lió a l’estudiar la gravetat, la durada i els resultats de les guerres civils; a més, contribueixen a una millor comprensió de la contribució històrica de la guerra irregular a la construcció de l’Estat i al canvi social.

The Determinants of Urban (Un)employment Duration: Evidence from Barcelona

This paper analyses the likelihood of leaving and joining employment in an urban area. Estimates show that individual, firm, regulatory and macroeconomic factors a ffect urban (un)employment duration in di fferent degrees. Also, national and urban (un)employment seem to share a common baseline hazard and similar macroeconomic and regulatory drivers. Individual characteristics are the only source of di fference we can identify between national and urban (un)employment duration. Keywords: Duration Models, Urban (Un)employment. JEL Classi fication: J64, R23.

Methodology for studying the numerical speed of sound in finite differences schemes

The space and time discretization inherent to all FDTD schemesintroduce non-physical dispersion errors, i.e. deviations ofthe speed of sound from the theoretical value predicted bythe governing Euler differential equations. A generalmethodologyfor computing this dispersion error via straightforwardnumerical simulations of the FDTD schemes is presented.The method is shown to provide remarkable accuraciesof the order of 1/1000 in a wide variety of twodimensionalfinite difference schemes.

Transition probabilities and duration analysis among disability states: Some evidence from Spanish data

In this paper we study the disability transition probabilities (as well as the mortalityprobabilities) due to concurrent factors to age such as income, gender and education. Althoughit is well known that ageing and socioeconomic status influence the probability ofcausing functional disorders, surprisingly little attention has been paid to the combined effectof those factors along the individuals' life and how this affects the transition from one degreeof disability to another. The assumption that tomorrow's disability state is only a functionof the today's state is very strong, since disability is a complex variable that depends onseveral other elements than time. This paper contributes into the field in two ways: (1) byattending the distinction between the initial disability level and the process that leads tohis course (2) by addressing whether and how education, age and income differentially affectthe disability transitions. Using a Markov chain discrete model and a survival analysis, weestimate the probability by year and individual characteristics that changes the state of disabilityand the duration that it takes its progression in each case. We find that people withan initial state of disability have a higher propensity to change and take less time to transitfrom different stages. Men do that more frequently than women. Education and incomehave negative effects on transition. Moreover, we consider the disability benefits associatedto those changes along different stages of disability and therefore we offer some clues onthe potential savings of preventive actions that may delay or avoid those transitions. Onpure cost considerations, preventive programs for improvement show higher benefits thanthose for preventing deterioration, and in general terms, those focussing individuals below65 should go first. Finally the trend of disability in Spain seems not to change among yearsand regional differences are not found.

Fixed-term contracts and the duration distribution of unemployment

In the mid-1980s, many European countries introduced fixed-term contracts.Since then their labor markets have become more dynamic. This paper studiesthe implications of such reforms for the duration distribution ofunemployment, with particular emphasis on the changes in the durationdependence. I estimate a parametric duration model using cross-sectionaldata drawn from the Spanish Labor Force Survey from 1980 to 1994 to analyzethe chances of leaving unemployment before and after the introduction offixed-term contracts. I find that duration dependence has increased sincesuch reform. Semi-parametric estimation of the model also shows that forlong spells, the probability of leaving unemployment has decreased sincesuch reform.

The effects of uncertainty avoidance on brand performance: Marketing creativity, product innovation and the brand duration

This paper investigates the link between brand performance and cultural primes in high-risk,innovation-based sectors. In theory section, we propose that the level of cultural uncertaintyavoidance embedded in a firm determine its marketing creativity by increasing the complexityand the broadness of a brand. It determines also the rate of firm product innovations.Marketing creativity and product innovation influence finally the firm marketingperformance. Empirically, we study trademarked promotion in the Software Security Industry(SSI). Our sample consists of 87 firms that are active in SSI from 11 countries in the period1993-2000. We use the data coming from SSI-related trademarks registered by these firms,ending up with 2,911 SSI-related trademarks and a panel of 18,213 observations. We estimatea two stage model in which first we predict the complexity and the broadness of a trademarkas a measure of marketing creativity and the rate of product innovations. Among severalcontrol variables, our variable of theoretical interest is the Hofstede s uncertainty avoidancecultural index. Then, we estimate the trademark duration with a hazard model using thepredicted complexity and broadness as well as the rate of product innovations, along with thesame control variables. Our evidence confirms that the cultural avoidance affects the durationof the trademarks through the firm marketing creativity and product innovation.

Unemployment duration and workers' wage aspirations in Spain

This paper examines unemployed workers' declared willingness to work for a wage lower than the one warranted by their qualification. We analyze which personal and economic characteristics determine thiswillingness and how it changes as unemployment spells lengthen. Moreover, we also study the influence of this willingness on unemployment duration. The main results are: (i) Young workers, those less educated and those living in regions with high unemployment show a more positive attitude towards accepting lower wages while married women with a working husband show more negative attitudes; (ii) The exhaustion of unemployment benefits has positive effects in the transition probability of the attitude from negative to positive; (iii) The effect of this attitude on the unemployment hazard rate is positive but only marginally significant which may be showing that this willingness is not only reflecting the worker's reservation wage but also some unobserved heterogeneity; (iv) The negative duration dependence of the unemployment hazard rate is substantially reduced when unobserved heterogeneity is controlled for.

Political economy of municipal water service privatization in Spain: a duration model analysis

This empirical work applies a duration model to the study of factors determining privatization of local water services. I assess how factors determining privatization decision evolve as time goes by. A sample of 133 Spanish municipalities during the six terms of office taken place during the 1980-2002 period is analyzed. A dynamic neighboring effect is hypothesized and successfully tested. In a first stage, private water supply firms may try to expand to regions where there is no service privatized, in order to spread over this region after having being installed thanks to its scale advantages. Other factors influencing privatization decision evolve during the two decades under study, from the priority to fix old infrastructures to the concern about service efficiency. Some complementary results regarding political and budgetary factors are also obtained

On the complementariness of infrasound and seismic sensors for monitoring snow avalanches

The paper analyses and compares infrasonic and seismic data from snow avalanches monitored at the Vallée de la Sionne test site in Switzerland from 2009 to 2010. Using a combination of seismic and infrasound sensors, it is possible not only to detect a snow avalanche but also to distinguish between the different flow regimes and to analyse duration, average speed (for sections of the avalanche path) and avalanche size. Different sensitiveness of the seismic and infrasound sensors to the avalanche regimes is shown. Furthermore, the high amplitudes observed in the infrasound signal for one avalanche were modelled assuming that the suspension layer of the avalanche acts as a moving turbulent sound source. Our results show reproducibility for similar avalanches on the same avalanche path.

The impact of the Spanish economic crisis on the duration of sickness absence

Directors: Jordi Delclós Clanchet, Mònica Ubalde López, Eva Calvo Bonacho