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This paper focuses on time series with long-memory and suggests using an alternative periodogram, called M-periodogram, which is obtained by relating the periodogram to a regression problem and then using an M-estimator for the coefficients of the regression model. The asymptotic properties of this novel M-periodogram are established and its empirical properties are investigated for finite samples under different scenarios. Furthermore, in addition to being an appealing alternative periodogram for long-memory time series, it is also resistant to additive outliers. We investigate the robustness performance of the estimator through simulation. As a practical application, the paper investigates the effect of atypical observations in air pollution data, namely daily Particulate Matter () observations. Besides the importance of modelling and forecasting this pollutant, the series presents, in general, interesting features such as seasonal poles, asymmetry, and also high levels of pollution which can be regarded as atypical observations in the context of this work. [ABSTRACT FROM AUTHOR]

Copyright of Hydrological Sciences Journal/Journal des Sciences Hydrologiques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrological Sciences Journal/Journal des Sciences Hydrologiques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrological Sciences Journal/Journal des Sciences Hydrologiques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper concerns robust location and scale estimators under long-range dependence, focusing on the Hodges-Lehmann location estimator, on the Shamos-Bickel scale estimator and on the Rousseeuw-Croux scale estimator. The large sample properties of these estimators are reviewed. This paper includes computer simulation in order to examine how well the estimators perform at finite sample sizes. [ABSTRACT FROM AUTHOR]

We propose a new approach for dealing with the estimation of the location of change-points in one-dimensional piecewise constant signals observed in white noise. Our approach consists in reframing this task in a variable selection context. We use a penalized least-square criterion with a ℓ1-type penalty for this purpose. We explain how to implement this method in practice by using the LARS / LASSO algorithm. We then prove that, in an appropriate asymptotic framework, this method provides consistent estimators of the change points with an almost optimal rate. We finally provide an improved practical version of this method by combining it with a reduced version of the dynamic programming algorithm and we successfully compare it with classical methods. [ABSTRACT FROM AUTHOR]

The Diagnostic Script Questionnaire (DSQ) is innovative in its format and its scoring process. It stems from the hypothetico-deductive reasoning and the illness script theories. In this exploratory study arguments favouring a progressive construction of illness scripts along with clinical experience were sought and the possible use of the script concept was tested to assess clinical competence. The research was conducted in radiology. The investigation used the radiological hyperlucent unilateral hemithorax syndrome as diagnostic challenge. The questionnaire was answered by three groups of participants: nine seasoned radiologists (with at least three years of experience), seven radiology residents (from year 1 to year 5), and 14 clerkship students who completed the questionnaire at the end of their radiology rotation. The data support the hypothesis of a progressive construction of specialized memory structures from students to seasoned radiologists. The DSQ was able to discriminate among participants according to their expected level of diagnostic clinical competence. [ABSTRACT FROM AUTHOR]

French-Canadian adolescent boys (n = 272) and girls (n = 286) participated in a study of the relationship between anomie and selected personal variables. Results of a multivariate regression analysis indicate that adolescents who suffered from anomie tended to be younger boys and girls with low self-esteem who believed that they were subject to chance or fate and who had experienced a number of recent negative life events. [ABSTRACT FROM AUTHOR]