Search

Sensitivity to auditory rhythmic structures in music and language is evident as early as infancy, but performance on beat perception tasks is often well below adult levels and improves gradually with age. While some research has suggested the ability to perceive musical beat develops early, even in infancy, it remains unclear whether adult-like perception of musical beat is present in children. The capacity to sustain an internal sense of the beat is critical for various rhythmic musical behaviors, yet very little is known about the development of this ability. In this study, 223 participants ranging in age from 4 years to 23 years from the Las Vegas, Nevada community completed a musical beat discrimination task, during which they first listened to a strongly metrical musical excerpt and then attempted to sustain their perception of the musical beat while listening to a repeated, beat-ambiguous rhythm for up to 14.4 s. They then indicated whether a drum probe matched or did not match the beat. Results suggested that the ability to identify the matching probe improved throughout middle childhood (8-9 years) and did not reach adult-like levels until adolescence (12-14 years). Furthermore, scores on the beat perception task were positively related to phonological processing, after accounting for age, short-term memory, and music and dance training. This study lends further support to the notion that children’s capacity for beat perception is not fully developed until adolescence and suggests we should reconsider assumptions of musical beat mastery by infants and young children.

Recently, many papers have shown evidence of a positive association between financial market participation and wealth holdings. It is often claimed that individuals with a higher level of financial market participation exhibit a higher propensity for planning retirement. In their planning process, individuals seek to achieve an optimal wealth level before their retirement by considering both their average saving rate and their retirement age. In this paper, we tested whether UK individuals with a higher level of financial market participation and, therefore, with a higher propensity for planning retirement were more likely to delay their retirement age than individuals with lower financial participation. On the basis of regression analyses using the English Longitudinal Study of Aging (ELSA) database for waves 1-6, our results support the hypothesis of a positive relationship between financial market participation and retirement age, reinforcing previous results., This study was funded by the Spanish Government MCIN/AEI/10.13039/501100011033, Grant PID2020-114563GB-I00, and Research Projects UHUPI00005-1085 for the promotion of basic knowledge-Research and Transfer Policy Strategy 2021 at University of Huelva (Spain).

Published on 06 Feb 2022 The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in children’s learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and children’s language development. The vocabularies of 1742 children aged 8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries (from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their child’s development, or vocabulary development benefited from intense caregiver-child interaction during lockdown, or both. We discuss these results in the context of the extraordinary circumstances of the COVID-19 pandemic and highlight limitations of the study. Funding for Polish sample: grant from National Science Center NCN (Poland), no 2018/31/B/HS6/03916. NK was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme [project number 223265].

Both humans and non-humans (e.g. birds and primates) preferentially produce and perceive auditory rhythms with simple integer ratios. In addition, these preferences (biases) tend to reflect specific integer-ratio rhythms that are common to one’s cultural listening experience. To better understand the developmental trajectory of these biases, we estimated children’s rhythm biases across the entire rhythm production space of simple (e.g., ratios of 1, 2, and 3) three-interval rhythms. North American children aged 6-11 years completed an iterative rhythm production task, in which they attempted to tap in synchrony with repeating three-interval rhythms chosen randomly from the space. For each rhythm, the child’s produced rhythm was presented back to them as the stimulus, and over the course of 5 such iterations we used their final reproductions to estimate their rhythmic biases or priors. Results suggest that regardless of the initial rhythm, after 5 iterations, children’s tapping converged on rhythms with (nearly) simple integer ratios, indicating that, like adults, their rhythmic priors consist of rhythms with simple-integer ratios. Furthermore, the relative weights (or prominence of different rhythmic priors) observed in children were highly correlated with those of adults. However, we also observed some age-related changes, especially for the ratio types that vary most across cultures. In an additional rhythm perception task, children were better at detecting rhythmic disruptions to a culturally familiar rhythm (in 4/4 meter with 2:1:1 ratio pattern) than to a culturally unfamiliar rhythm (7/8 meter with 3:2:2 ratios), and performance in this task was correlated with tapping variability in the iterative task. Taken together, our findings provide evidence that children as young as 6-years-old exhibit simple integer-ratio categorical rhythm priors in their rhythm production that closely resemble those of adults in the same culture.

Synchronization of movement to music is a seemingly universal human capacity that depends on sustained beat perception. Previous research has suggested that listener's conscious perception of the musical structure (e.g., beat and meter) might be reflected in neural responses that follow the frequency of the beat. However, the extent to which these neural responses directly reflect concurrent, listener-reported perception of musical beat versus stimulus-driven activity is understudied. We investigated whether steady state-evoked potentials (SSEPs), measured using electroencephalography (EEG), reflect conscious perception of beat by holding the stimulus constant while contextually manipulating listeners' perception and measuring perceptual responses on every trial. Listeners with minimal music training heard a musical excerpt that strongly supported one of two beat patterns (context phase), followed by a rhythm consistent with either beat pattern (ambiguous phase). During the final phase, listeners indicated whether or not a superimposed drum matched the perceived beat (probe phase). Participants were more likely to indicate that the probe matched the music when that probe matched the original context, suggesting an ability to maintain the beat percept through the ambiguous phase. Likewise, we observed that the spectral amplitude during the ambiguous phase was higher at frequencies that matched the beat of the preceding context. Exploratory analyses investigated whether EEG amplitude at the beat-related SSEPs (steady state-evoked potentials) predicted performance on the beat induction task on a single-trial basis, but were inconclusive. Our findings substantiate the claim that auditory SSEPs reflect conscious perception of musical beat and not just stimulus features.

Synchronization of movement to music is a seemingly universal human capacity that depends on sustained beat perception. Previous research has suggested that listener’s conscious perception of the musical structure (e.g., beat and meter) might be reflected in neural responses that follow the frequency of the beat. However, the extent to which these neural responses directly reflect concurrent, listener-reported perception of musical beat versus stimulus-driven activity is understudied. We investigated whether steady state-evoked potentials (SSEPs), measured using electroencephalography (EEG), reflect conscious perception of beat by holding the stimulus constant while contextually manipulating listeners’ perception and measuring perceptual responses on every trial. Listeners with minimal music training heard a musical excerpt that strongly supported one of two beat patterns (context phase), followed by a rhythm consistent with either beat pattern (ambiguous phase). During the final phase, listeners indicated whether or not a superimposed drum matched the perceived beat (probe phase). Participants were more likely to indicate that the probe matched the music when that probe matched the original context, suggesting an ability to maintain the beat percept through the ambiguous phase. Likewise, we observed that the spectral amplitude during the ambiguous phase was higher at frequencies that matched the beat of the preceding context. Exploratory analyses investigated whether EEG amplitude at the beat-related SSEPs predicted performance on the beat induction task on a single-trial basis, but were inconclusive. Our findings substantiate the claim that auditory steady state-evoked potentials (SSEPs) reflect conscious perception of musical beat and not just stimulus features.

Both target papers cite evidence from infancy and early childhood to support the notion of human musicality as a somewhat static suite of capacities; however, in our view they do not adequately acknowledge the critical role of developmental timing, the acquisition process, or the dynamics of social learning, especially during later periods of development such as middle childhood.

El objetivo de este trabajo es determinar el efecto directo que sobre las prestaciones por jubilacion tiene la reforma del sistema publico espanol de pensiones llevada a cabo recientemente. Aplicando Modelos de Micro Simulacion a una muestra de 5.025 vidas laborales de individuos que se jubilaron en 2011, se concluye que la reforma tiene una incidencia media negativa en las dos variables analizadas: la pension inicial y la edad de jubilacion. No obstante, cuando se analiza la incidencia por deciles, se observan en ambas variables efectos de distinta magnitud y signo, asi como una elevada correlacion entre dichos efectos.

This paper proposes the mixed frequency conditional beta. We employ the MIDAS framework to estimate market betas as a weighted average of a high and low frequency components. Then, we analyze the macroeconomic determinants of stock market betas and the counter- or pro-cyclicality of betas across well-known portfolio sorts. The surplus consumption ratio with time-varying risk aversion and the default premium are the aggregate variables with the higher statistical impact on stock market betas across alternative portfolios. We show the implications of the mixed frequency betas for the term structure of holding-period expected excess returns, and for alternative investment strategies.

Understanding the neural underpinning of conscious perception remains one of the primary challenges of cognitive neuroscience. Theories based mostly on studies of the visual system differ according to whether the neural activity giving rise to conscious perception occurs in modality-specific sensory cortex or in associative areas, such as the frontal and parietal cortices. Here, we search for modality-specific conscious processing in the auditory cortex using a bistable stream segregation paradigm that presents a constant stimulus without the confounding influence of physical changes to sound properties. ABA_ triplets (i.e., alternating low, A, and high, B, tones, and _ gap) with a 700 ms silent response period after every third triplet were presented repeatedly, and human participants reported nearly equivalent proportions of 1- and 2-stream percepts. The pattern of behavioral responses was consistent with previous studies of visual and auditory bistable perception. The intermittent response paradigm has the benefit of evoking spontaneous perceptual switches that can be attributed to a well-defined stimulus event, enabling precise identification of the timing of perception-related neural events with event-related potentials (ERPs). Significantly more negative ERPs were observed for 2-streams compared to 1-stream, and for switches compared to non-switches during the sustained potential (500-1000 ms post-stimulus onset). Further analyses revealed that the negativity associated with switching was independent of switch direction, suggesting that spontaneous changes in perception have a unique neural signature separate from the observation that 2-streams has more negative ERPs than 1-stream. Source analysis of the sustained potential showed activity associated with these differences originating in anterior superior temporal gyrus, indicating involvement of the ventral auditory pathway that is important for processing auditory objects.Significance StatementWhen presented with ambiguous stimuli, the auditory system takes the available information and attempts to construct a useful percept. When multiple percepts are possible from the same stimuli, however, perception fluctuates back and forth between alternating percepts in a bistable manner. Here, we examine spontaneous switches in perception using a bistable auditory streaming paradigm with a novel intermittent stimulus paradigm, and measure sustained electrical activity in anterior portions of auditory cortex using event-related potentials. Analyses revealed enhanced sustained cortical activity when perceiving 2-streams compared to 1-stream, and when a switch occurred regardless of switch direction. These results indicate that neural responses in auditory cortex reflect both the content of perception and neural dynamics related to switches in perception.

We estimate the implied equity duration using industry‐specific parameters. We provide evidence that this procedure improves the ability of implied equity duration to capture stock price risk. We show that it is due to a better capture of both the market risk and residual risk of the market asset pricing model. As expected, the higher the difference in the estimates of duration, the higher the improvement in measuring price risk, but the results also show that the highest improvements are obtained when the usual implied equity duration estimation based on market parameters performs poorly as a price risk measure.

How do uncertainty and risk aversion affect the behavior of investment-style factors? We argue that a significant channel through which both uncertainty and risk aversion impact aggregate risk factors is the exposure of factor returns to real activity. We analyze this issue using mixed data sampling decomposition of the sensitivity of factor returns to real activity into high- and low-frequency components. We find a positive and significant relation between uncertainty and risk aversion for the low-frequency component of the sensitivity of factor returns to economic activity. More importantly, risk aversion significantly amplifies the effects of uncertainty on real activity exposure. The quality-based factor is an important exception to these findings.

For multivariate time series modelling, it is essential to know the number of common factors that define the behaviour. The traditional approach to this problem is investigating the number of cointegration relations among the data by determining the trace and the maximum eigenvalue and obtaining the number of stationary long-run relations. Alternatively, this problem can be analyzed using dynamic factor models, which involves estimating the number of common factors, both stationary and not, that describe the behaviour of the data. In this context, we empirically analyze the power of such alternative approaches by applying them to time series that are simulated using known factorial models and to financial market data. The results show that when there are stationary common factors, when the number of observations is reduced and/or when the variables are part of more than one cointegration relation, the common factors test is more powerful than the usually applied cointegration tests. These results, together with the greater flexibility to identify the loading matrix of the data generating process, render dynamic factor models more suitable for use in multivariate time series analysis. Para la modelización multivariante de series temporales no estacionarias es imprescindible conocer el número de factores comunes que definen el comportamiento de las series. La forma tradicional de abordar este problema es el estudio de las relaciones de cointegración entre los datos a través de las pruebas de la traza y el máximo valor propio, obteniendo el número de relaciones de largo plazo estacionarias. Como alternativa, se pueden emplear modelos factoriales dinámicos que estiman el número de factores comunes, estacionarios o no, que describen el comportamiento de los datos. En este contexto, analizamos empíricamente el resultado de aplicar tales métodos a series simuladas mediante modelos factoriales conocidos, y a datos reales de los mercados financieros. Los resultados muestran que cuando hay factores comunes estacionarios, cuando el número de observaciones se reduce y/o cuando las variables participan en más de una relación de cointegración, la prueba de factores comunes es más potente que las pruebas habituales de cointegración. Estos resultados, junto con la mayor flexibilidad para identificar la matriz de cargas del proceso generador de datos, hacen que los modelos de factores dinámicos sean más adecuados para su utilización en el análisis multivariante.

Purpose – In this paper, the authors aim to analyze the impact of International Financial Reporting Standards' (IFRS) mandatory adoption on the financial statements of Spanish listed companies. Design/methodology/approach – The authors estimate a panel data model by generalized least squares' within-between in order to contrast the possible structural breaks in the relations between income statement items and balance sheet items, using data from the 35 largest listed companies. Findings – The results show significant changes on these relations, but with different signs and degrees of intensity depending on the balance sheet item analyzed. Research limitations/implications – The data choice introduces a size bias that could be taken into account in the generalization of the results to other listed companies. Originality/value – This work is developed using a mandatory, local, accounting and panel data framework for first time using Spanish listed companies in order to measure the impact of the IFRS adoption.

The purpose of this study was to identify areas of abnormal white matter microstructure in adolescents with Major Depressive Disorder (MDD) using diffusion tensor imaging (DTI). Fractional anisotropy (FA) values representing preferential diffusivity along major tracts were examined using tract-based spatial statistics across the whole brain in adolescents ages 13-19 with MDD (n = 31) compared with demographically-matched healthy controls (n = 31). We not only examined frontal lobe tracts that have been most frequently identified as abnormal in previous DTI studies of older depressed patients, but also tested for FA group differences across the whole brain to determine if adolescent depression was related to any other regional white matter abnormality. MDD-diagnosed adolescents had significantly lower FA in many regions concentrated predominantly in the frontal lobe. There also was strong evidence for lower FA in bilateral anterior/posterior limbs of the internal capsules, as well as tracts through the midbrain, left external capsule, right thalamic radiation and left inferior longitudinal fasciculus. Consistent with previous findings in depressed young and elderly adults, the current study found evidence for abnormal microstructure in white matter connections of the frontal lobe in MDD adolescents. There also was strong evidence for FA abnormalities in corpus callosum genu, internal and external capsule tracts, thalamus and midbrain, notable for both the relative magnitude of these effects and absence from most previous white matter studies of depression. These abnormalities might represent important markers of early life-onset depression.

The available evidence indicates that the music of a culture reflects the speech rhythm of the prevailing language. The nPVI (normalized pairwise variability index) is a measure of durational contrast between successive events that can be applied to vowels in speech and to notes in music. Music–language parallels may have implications for the acquisition of language and music, but it is unclear whether native-language rhythms are reflected in children’s songs. In general, children’s songs exhibit greater rhythmic regularity than adults’ songs, in line with their caregiving goals and frequent coordination with rhythmic movement. Accordingly, one might expect lower nPVI values (i.e., lower variability) for such songs regardless of culture. In addition to their caregiving goals, children’s songs may serve an intuitive didactic function by modelling culturally relevant content and structure for music and language. One might therefore expect pronounced rhythmic parallels between children’s songs and language of origin. To evaluate these predictions, we analyzed a corpus of 269 English and French songs from folk and children’s music anthologies. As in prior work, nPVI values were significantly higher for English than for French children’s songs. For folk songs (i.e., songs not for children), the difference in nPVI for English and French songs was small and in the expected direction but non-significant. We subsequently collected ratings from American and French monolingual and bilingual adults, who rated their familiarity with each song, how much they liked it, and whether or not they thought it was a children’s song. Listeners gave higher familiarity and liking ratings to songs from their own culture, and they gave higher familiarity and preference ratings to children’s songs than to other songs. Although higher child-directedness ratings were given to children’s than to folk songs, French listeners drove this effect, and their ratings were uniquely predicted by nPVI. Together, these findings suggest that language-based rhythmic structures are evident in children’s songs, and that listeners expect exaggerated language-based rhythms in children’s songs. The implications of these findings for enculturation processes and for the acquisition of music and language are discussed.

This paper proposes the mixed frequency conditional beta. We employ the MIDAS framework to decompose market betas into high and low frequency components. The total mixed frequency beta is the weighted average of these two components. Then, we analyze the macroeconomic determinants of stock market betas, and the counter or pro-cyclicality of betas across well-known portfolio sorts. The surplus consumption ratio with time-varying risk aversion and the default premium are the aggregate variables with the higher statistical impact on stock market betas across alternative portfolios.

Hoarding Disorder (HD) is a common and chronic condition that is associated with distinct abnormalities in neural function. The impact of treatment on these abnormalities is not known. Six patients with HD and 6 healthy control (HC) participants underwent a functional magnetic resonance imaging (fMRI) task in which they made simulated decisions about whether to acquire or discard a variety of objects. The HD patients then received 16 sessions of manualized group cognitive behavioral therapy (CBT) for HD. After treatment, the HD patients completed the same fMRI decision-making tasks to identify changes in brain function elicited by decision-making. During acquiring decisions, reductions in HD patients' hemodynamic activity were observed in medial frontal gyrus, anterior and posterior cingulate, left insular cortex/postcentral gyrus, right caudate and putamen, paracentral lobule, bilateral posterior parietal lobe regions, right superior temporal gyrus, left hippocampus/parahippocampus, occipital cortex, and anterior cerebellum. During discarding decisions, reduced activity was observed in right superior/medial frontal gyri, left insula/putamen, posterior cingulate, precuneus, right posterior hippocampus, lingual/cuneus and right putamen. Prior to treatment, activity in these regions differed significantly between HD patients and HC participants. However, after CBT, most of these differences were no longer significant, suggesting normalization of neural function.

The present study introduces a balanced survey of a range of behavioral and emotional experiences to assess impressions of a person’s childhood. Ninety-one undergraduates and 70 of their parents rated exposure to positive and negative social and solitary experiences. The survey demonstrated acceptable internal consistency and 4-week test–retest reliability, and scores correlated with Zimbardo’s Time Perspective Inventory of temporally based beliefs and values, Batcho’s inventory of personal nostalgia, and Holbrook’s measure of historical nostalgia. Correlations with time perspective and nostalgia inventories suggest that favorable impressions of childhood are associated with benefits such as social connectedness, personal continuity, and health-promoting behaviors and adverse impressions with less adaptive impacts such as unsatisfactory relationships, discontinuity, and distress. Ratings of social experiences were correlated more closely with childhood happiness than were solitary experiences. The Childhood Survey shows promise as a tool to expand the exploration of childhood experiences beyond adverse events to encompass components that comprise a happy childhood.

The term structure of interest rates is a key instrument for financial research. It provides relevant information for pricing deterministic financial cash flows, it measures economic market expectations and it is extremely useful when assessing the effectiveness of monetary policy decisions. However, it is not directly observable and needs to be estimated by smoothing asset pricing data through statistical techniques. The most popular techniques adjust parsimonious functional forms based on bond yields to maturity. Unfortunately, these functions, which need to be optimised, are highly non-linear which make them very sensitive to the initial conditions. In this context, this paper proposes the use of genetic algorithms to find the values for the initial conditions and to reduce the risk of false convergence, showing that stable parameters are obtained without imposing arbitrary restrictions.

Hydrogels have been the focus of considerable interest for use in a range of applications including bioseparations, controlled release devices, and artificial organs. While they have attractive properties, hydrogels typically provide limited selectivity and have low protein loading. Metal affinity ligands were grafted to poly (vinyl alcohol) hydrogels to provide a selective means to enhance protein loading and improve protein separation characteristics. The impact of solution conditions on the solubility and transport properties of chicken egg white lysozyme (CEWL) and Ribonuclease A (RnaseA) were determined. The metal affinity ligands provided a selective means to increase CEWL and RnaseA loading. In addition, the solubility of CEWL and RnaseA were moderated by changes in either temperature or solution pH. The impact of metal affinity ligands and solution pH on the mass transfer coefficient of CEWL and RnaseA through the hydrogel membranes will be discussed.

The content of original song lyrics was manipulated to explore the relationship of nostalgia to identity and social connectedness. A sample of 96 undergraduates rated six attributes of four sets of lyrics and completed measures of identity exploration, styles of maintaining identity, nostalgia for t

This paper describes the evolution of the daily Euro overnight interestrate (EONIA) by using several models containing the jump component such asa single regime ARCH-Poisson-Gaussian process, with either a piecewisefunction or an autoregressive conditional specification (ARJI) for the jumpintensity, and a two regime-switching process with jumps and time varyingtransition probabilities. To model the jump intensity, we include the followingeffects which are significant for the occurrence of jumps such as: (1) the end ofmaintenance period effect because of reserve requirements, (2) the end ofmonth effect, also known as the calendar day effect, caused mainly by theaccounting adjustments and finally, (3) the meeting effect caused by thefortnightly meetings of the Governing Council of the European Central Bank(ECB). These effects lead to a better performance and several of them are alsoincluded for the behavior of the transition probabilities. Since the target of theECB is keeping the EONIA rate close to the official rate, we have modeled theconditional mean of the overnight rate series as a reversion process to theofficial rate distinguishing two alternative speeds of reversion, in concrete, adifferent speed if EONIA is higher or lower than the official rate. We also studythe jumps of the EONIA rate around the ECB’s meetings by using the ex-postprobabilities of the ARJI model. Finally, we develop an out-of-sampleforecasting analysis to measure the performance of the different candidatemodels.

Background: The aim of this study was to assess the validity of diagnosing attention deficit/hyperactivity disorder (ADHD) in high IQ children and to further characterize the clinical features associated with their ADHD. Methods: We operationalized giftedness/high IQ as having a full scale IQ ≥120. We identified 92 children with a high IQ who did not have ADHD and 49 children with a high IQ that met diagnostic criteria for ADHD who had participated in the Massachusetts General Hospital Longitudinal Family Studies of ADHD. Results: Of our participants with ADHD and a high IQ, the majority (n = 35) met criteria for the Combined subtype. Relative to control participants, children with ADHD and high IQ had a higher prevalence rate of familial ADHD in first-degree relatives, repeated grades more often, had a poorer performance on the WISC-III Block Design, had more comorbid psychopathology, and had more functional impairments across a number of domains. Conclusions: Children with a high IQ and ADHD showed a pattern of familiality as well as cognitive, psychiatric and behavioral features consistent with the diagnosis of ADHD in children with average IQ. These data suggest that the diagnosis of ADHD is valid among high IQ children.

We employ MIDAS (mixed data sampling) to study the risk–expected return trade-off in several European stock indices. Using MIDAS, we report that in most indices there is a significant positive relationship between risk and expected return. This strongly contrasts with the result we obtain when we employ both symmetric and asymmetric GARCH models for conditional variance. We also find that asymmetric specifications of the variance process within the MIDAS framework improve the relationship between risk and expected return. As an additional application, we analyze the extent to which European stock markets are integrated, which is a particularly relevant issue, especially following the launch of the Euro in January 1999. Finally, we propose a bivariate MIDAS specification to test the pricing significance of the hedging component within an intertemporal risk–return trade-off with multiple European market indices.

Since the seminal paper of Vasicek and Fong (1982), the term structures of interest rates have been fitted assuming that yields are cross-sectionally homoskedastic. We show that this assumption does not hold when there are differences in liquidity, even for bonds of the same issuer. Lower turnover implies higher volatility. In addition, a minimum tick size for bond price negotiation will produce higher volatility for bonds approaching their maturity dates. To show these effects, we use data for Spanish sovereign bonds from 1988 to 2010, covering more than 700 bonds and 5000 trading days. We estimate the out-of-sample error for each bond and day. The variance of these errors is found to be negatively correlated with each bond’s turnover and duration, while the mean of the errors is found to be directly correlated with the estimated variance. As a result, we propose a modified Svensson (1994) yield curve model to fit the term structure, adding a liquidity term and estimating parameters by weighted least-squared errors to take into account the liquidity-induced heteroskedasticity.

Dissolution of [CpRu(PPh 3 )(SC 4 H 8 ) 2 ]CF 3 SO 3 in thietane/CH 2 Cl 2 with stirring yields the title compound [CpRu(PPh 3 )(SC 3 H 6 ) 2 ]CF 3 SO 3 ( I ). The single crystal X-ray structure shows a disparity in the puckering of the two thietanes. One thietane ligand is near-planar, with torsion angles of ±1.5(5)° for CSCC and ±1.8(4)° for CCCS; the second thietane ligand of I has torsion angles of ±21.0(4)° for CSCC and ±25.0(3)° for CCCS. Compound I contains both the largest and the smallest torsion angles for any complex reported. Theoretical calculations were carried out for both thietane and for I using the gamess and gaussian 98 packages.

RESUMENEl objetivo de este trabajo es contrastar la existencia de primas por liquidez en los activos financieros de renta fija. Entre otros, Fama [1984] y Fama y Bliss [1987] intentaron determinar si los tipos de interes forward son buenos estimadores de los tipos de interes futuros, poniendo de manifiesto en el mercado estadounidense su pobre poder predictivo en el corto plazo. En el mercado espanol son varios los trabajos que han analizado este mismo problema en el corto plazo utilizando para ello datos del mercado interbancario. Por el contrario, en este trabajo se reexamina la presencia de primas temporales en la estructura temporal de tipos de interes utilizando estimaciones de la curva de bonos cupon-cero. Los resultados obtenidos son consistentes con los obtenidos en el mercado interbancario espanol y, a su vez, contradictorios con los obtenidos en el mercado estadounidense.

We analyze the empirical pattern of the Ohlson models (1995) focusing on four basic implicit assumptions that support the model: (i) the displacement property, (ii) the goodness of book value as a proxy of the ability of assets and liabilities to generate cash flows, (iii) the conservatism correction value, and (iv) the clean surplus relation. We test the long-term equilibrium relations on the Dow Jones Composite Index companies, using an Error Correction Model when non-stationary variables are present and a cointegration relation exists. The results show that for only slightly more than 10% of the companies we cannot simultaneously reject the four assumptions.

In a seminal paper, Dechow, Sloan and Soliman (2004) develop a price-implied measure for equity duration and for its estimation they employ parsimonious but relatively crude procedures. Hence, these authors claim that improvements in procedures should lead to more accurate and useful estimates of their measure. Within this context, we estimate the implied equity duration but using industry-specific parameters for forecasting and discounting the future cash flows of listed firms as opposed to the market-estimated parameters used previously. We show that when we move to estimation based on industry-specific parameters, significant differences arise in absolute, relative and rank terms. We also provide evidence that the new procedures improve the ability of implied equity duration to capture stock price risk. When we seek the source of this improvement, we find that it is due to a better capture of both the market risk and residual risk of the market asset-pricing model. As expected, the higher the difference in the estimates of duration, the higher the improvement in measuring price risk, but the results also show that the highest improvements are given when implied equity duration based on market parameters performs poorly as a price-risk measure. Thus, we conclude that the cost of being parsimonious in estimating firms' duration is high on average and also quite variable across firms, both quantitatively and qualitatively. Moreover, this cost is large enough to reverse the duration-based ranking order of firms and to result in estimated durations without the ability to measure price risk.

We analyze the relationship between the stance of monetary policy and the implicit risk aversion in European Stock market prices in an international open-economy framework. We use a structural vector autoregression (SVAR) model that incorporates the effect of a factor that reflects the global monetary policy stance. We use shocks in the US Fed monetary policy stance as a proxy of this global factor. Our results indicate mixed evidence depending on whether simultaneity between domestic monetary policy stance and the stock market behavior is taken into full account. When this simultaneity is not allowed we confirm previous evidence found in the literature, extended to the international field: a lax monetary policy, both domestic and global, decreases risk aversion. However, when we take this into account, results indicate that a lax monetary policy increase in the short-run the risk aversion of the domestic representative investor.