Parsimonious periodic autoregressive models for time series with evolving trend and seasonality

Statistics and Computing - This paper proposes an extension of Periodic AutoRegressive (PAR) modelling for time series with evolving features. The large scale of modern datasets, in fact, implies...     

Actions,habits and forms of life

After a survey on the work of prominent philosophers within the Western tradition, it can be noticed a tendency to view habits as automatic, unfree and unconscious behaviour. In this context, this article attempts to show that habits are actually much closer to the characteristics that are otherwise attributed to actions. That is, following the dialectical approach of Sartre, I develop arguments to support that habits are conscious actions carried out with a sense of identification towards the form of life that actions, in turn, project as a whole; in this way, each form of life requires a set of habits that the agent performs freely and rationally, understanding the latter as the dialectical procedure by which the act itself brings about a totalizing identity. This vision implies that habits are interrelated and codependent within a network of social behavior, so they cannot be discarded without discarding the form of life to which they belong. That is, a change of habit requires a change in the totality of which it is a part. But that change can only occur if social agents become aware that their habits are a product of their free acceptance and not of necessity. In the article, this latter is paradigmatically exemplified by neoliberal capitalism as a form of life.     

Monitoring Progress in Child Poverty Reduction: Methodological Insights and Illustration to the Case Study of Bangladesh

Important steps have been taken at international summits to set up goals and targets to improve the wellbeing of children worldwide. Now the world also has more and better data to monitor progress. This paper presents a new approach to monitoring progress in child poverty reduction based on the Alkire and Foster adjusted headcount ratio and an array of complementary techniques. A theoretical discussion is accompanied by an assessment of child poverty reduction in Bangladesh based on four rounds of the demographic household survey (1997–2007). Emphasis is given to dimensional monotonicity and decomposability as desirable properties of multidimensional poverty measures. Complementary techniques for analysing changes over time are also illustrated, including the Shapley decomposition of changes in overall poverty, as well as a range of robustness tests and statistical significance tests. The results from Bangladesh illustrate the value added of these new tools and the information they provide for policy. The analysis reveals two paths to multidimensional poverty reduction by either decreasing the incidence of poverty or its intensity, and exposes an uneven distribution of national gains across geographical divisions. The methodology allows an integrated analysis of overall changes yet simultaneously examines progress in each region and in each dimension, retaining the positive features of dashboard approaches. The empirical evidence highlights the need to move beyond the headcount ratio towards new measures of child poverty that reflect the intensity of poverty and multiple deprivations that affect poor children at the same time.     

Spanish validation of the Servant Leadership Short Scale for young adults and adolescents / Validación de la Escala de Liderazgo de Servicio Versión Abreviada en español para jóvenes adultos y adolescentes

The aim of the current study was to validate a shortened Spanish version of the Servant Leadership Profile (SLP). In Study 1, a number of experts evaluated and reduced the original scale to 14 items and named the revised version the Servant Leadership Short Scale (SLSS). An exploratory factor analysis conducted with a sample of 1,001 students revealed two possible structure solutions, a one-factor solution and a two-correlated factor solution. Study 2 used a different sample of 456 students to examine the explored structures using confirmatory factor analysis. A one-factor solution was proposed (χ²/df = 3.4, CFI = .91, TLI = .90, RMSEA = .07, SRMR = .06). Finally, in Study 3, servant leadership was used as a predictor of self-efficacy (b = .685, p < .001) and demonstrated good predictive validity. This model explained 41.55% of the variance on self-efficacy. Reliability analyses of the three studies showed that this 14-item Spanish version had high internal consistency. Together, the results of the three studies support the application of the SLSS in future research.     

SEPARATING BETWEEN UNOBSERVED CONSUMER TYPES: EVIDENCE FROM AIRLINES

We propose an alternative approach to identify unobserved consumer types and assess whether firms price discriminate. Unlike other screening schemes that rely on quantity discounts or product differentiation, in our finite mixture structure individuals have unit demands and the product is homogeneous. We implement the model using an original U.S. airlines data set. The results support the existence of two demand types. The high‐type “business” traveler is less price sensitive, has a higher valuation, and pays a higher price than the low type “tourist.” The proportion of high types also increases as the departure date nears. (JEL C23, L93, R41)     

Una conversación con Michael Billig

Resumen

Este estudio explora el impacto del 11-M en las reacciones emocionales, las formas de afrontamiento y el riesgo percibido en la población española. Han participado 869 personas (el 42,7% cumplimentó el cuestionario antes de los atentados y el 57,3% después). Tras el 11-M aumenta la percepción de riesgo, la intensidad emocional negativa y las conductas de afrontamiento defensivo. Existe una sobreestimación del riesgo personal respecto a la probabilidad real. Los participantes más expuestos a situaciones de riesgo (País Vasco) son los que presentan menor probabilidad de ser víctimas del evento. El miedo induce a adoptar estrategias de tipo defensivo y refuerza la percepción de riesgo mientras que la cólera se asocia a reacciones agresivas. Los resultados confirman que las personas atribuyen respuestas afectivas y formas de afrontamiento más disfuncionales a los otros que a uno mismo. Existe una relativa independencia entre la experiencia directa y la percepción de riesgo. El 11-M no ha repercutido ni en la benevolencia ni en la confianza que se tiene en los otros ni en las creencias de tipo socio-cultural.     

A test for randomness based on a complexity measure

A test for randomness based on a statistic related to the complexity of finite sequences is presented. Simulation of binary sequences under different stochastic models provides estimates of the power of the test. The results show that the test is sensitive to a variety of alternatives to randomness and suggest that the proposed test statistic is a reasonable measure of the stochastic complexity of a finite sequence of discrete random variables.     

Audit committee and internal audit and the quality of earnings: empirical evidence from Spanish companies

Corporate scandals and failures such as Enron, WorldCom, etc. were highly catastrophic and had a terrible effect on stakeholders. The pressure of globalisation and the intense competition have lead to organisations encouraging good corporate governance. Organisations have to promote transparency and accountability of financial information. As Gramling et al. (J Account Lit 23:194–244, 2004) argued there are four important mechanisms of corporate governance include boards of directors, audit committees (among others) and internal and external audit functions. However, this paper will focus on the relationship between two corporate governance mechanisms (audit committee and internal audit function). Thus, our purpose is to analyse the relation between characteristics of the audit committee and internal audit function and earnings management measured as abnormal accruals to test the quality of financial statements. We hypothesise that the association between the effectiveness of the audit committee and the presence of an internal audit function and its relationship with this committee would indicate less opportunity for management to manipulate earnings. Using a sample of 108 non-financial Spanish companies that traded on the Madrid Stock Exchange between 2003 and 2006 (432 observations), we have found that the size and number of meetings of the audit committee had a significant negative association with earnings manipulations. Also, our results suggest that a negative relation between having an internal audit function and earnings management.     

MOMENT ESTIMATION IN THE CLASS OF BISEXUAL BRANCHING PROCESSES WITH POPULATION–SIZE DEPENDENT MATING

This paper concerns the estimation of the offspring mean vector, the covariance matrix and the growth rate in the class of bisexual branching processes with population‐size dependent mating. For the proposed estimators, some unconditional moments and some conditioned to non‐extinction are determined and asymptotic properties are established. Confidence intervals are obtained and, as illustration, a simulation example is given.