Search results for "selection"

A System of Indicators for Evaluating Public Broadcasting Corporations

2018

We describe an operational procedure to build an integrated information system (IIS) for monitoring and evaluating the performance of public broadcasting corporations (PBC). The procedure grounds in a conceptual framework derived from evaluation models, and consists of two stages. The first stage is the selection, through expert judgment, of simple indicators that illustrate the most relevant aspects of the corporations. The second stage is the definition of a system of indicators related to each level of the hierarchy of objectives planned by the corporations. The system of indicators has two levels. The first level is a basic indicator system that allows description and monitoring of the …

Penalized regression and clustering in high-dimensional data

The main goal of this Thesis is to describe numerous statistical techniques that deal with high-dimensional genomic data. The Thesis begins with a review of the literature on penalized regression models, with particular attention to least absolute shrinkage and selection operator (LASSO) or L1-penalty methods. L1 logistic/multinomial regression models are used for variable selection and discriminant analysis with a binary/categorical response variable. The Thesis discusses and compares several methods that are commonly utilized in genetics, and introduces new strategies to select markers according to their informative content and to discriminate clusters by offering reduced panels for popul…

Estimating the Number of Changepoints in Segmented Regression Models: Comparative Study and Application

2020

This paper deals with the problem of selecting the number of changepoints in segmented regression models. The aim is to review selection criteria, namely information criteria and hypothesis testing, and to propose a novel application in the context of students' careers in higher education. The performance of the selection criteria is assessed through simulation studies. Furthermore, we investigate the relationship between University students' performance and one of its main determinants, finding out that this relationship is actually broken-line.

The Relationship between General Intelligence and Media Use among University Students

2020

Students’ information selection process might be influenced by their choice of media sources, their learning contexts and motivation to use certain media as well as their general intelligence, which is crucial for information processing. This study examines the relationship between the general fluid intelligence and the media use of 709 first-year business & economics students from 44 universities in Germany for two different learning purposes: informing oneself about B&E topics and preparing for lectures and exams. Accordingly, the motivator information seeking is divided into curiosity driven and goal driven information seeking. Three types of media sources were included: common news sour…

An investigation of the pharmacological applications used for the Ancient Egyptian systemic model ‘ra-ib’ compared with modern Traditional Chinese Me…

2020

Abstract Ethnopharmacological relevance Ancient Egyptian texts only offer glimpses into their conceptual understandings of the inner-body and illness manifestation. Explanations of how prescribed materia medica were believed to work are rare and obscure, often resulting in modern approximations for ancient terminology such as ‘ra-ib’—an ancient Egyptian classification predominantly translated as ‘stomach’—leading to misunderstandings of historical texts, and therefore their use of pharmacology. Aim of the study To investigate the ra-ib and the explanatory models of illness from the Egyptian perspective, and to explore the link between these and the prescribed selection of materia medica. To…

Effect of organic loading rate on the production of Polyhydroxyalkanoates from sewage sludge

2023

The aim of this work was to study the effect of organic loading rate on the production of Polyhydroxyalkanoates (PHA) from sewage sludge. Synthesis of PHA using sewage sludge as platform was achieved in this work. Three pilot-scale selection-sequencing batch reactors (S-SBR) were used for obtaining a culture able to accumulate PHA following a strategy of aerobic dynamic feeding (ADF) at different volumetric organic-loading-rate (vOLR): 1.3, 1.8 and 0.8 g COD L-1 d-1 for S-SBR 1, S-SBR 2 and S-SBR 3, respectively. Decreasing the vOLR enhanced the general performance of the process as for organic matter removal (from 99.2% ± 0.3% in S-SBR-3 to 92 ± 2 in S-SBR-2) while the opposite trend was r…

A metaphysical approach to holobiont individuality: Holobionts as emergent individuals

2019

Holobionts are symbiotic assemblages composed by a host plus its microbiome. The status of holobionts as individuals has recently been a subject of continuous controversy, which has given rise to two main positions: on the one hand, holobiont advocates argue that holobionts are biological individuals; on the other, holobiont detractors argue that they are just mere chimeras or ecological communities, but not individuals. Both parties in the dispute develop their argu-ments from the framework of the philosophy of biology, in terms of what it takes for a ?conglomerate? to be considered an interesting individual from a biological point of view. However, the debates about holobiont individualit…

¿SE PUEDE MEDIR LA NEGOCIACIÓN INFORMADA?: UNA REVISIÓN DE LA METODOLOGÍA BASADA EN LAS COVARIANZAS DE LAS SERIES DE PRECIOS / CAN WE MEASURE THE INS…

2009

El desarrollo en los modelos teóricos de microestructura ha motivado la aparición de un grupo de trabajos encaminado al estudio empírico de los costes de transacción y sus componentes dada la importancia que han tenido los mismos en el estudio del funcionamiento de los mercados y la comparación entre éstos así como sus numerosas aplicaciones en campos afines (finanzas corporativas, eficiencia de los mercados, etc.). Por otra parte, la contrastación empírica de los distintos modelos establecidos muestra resultados claramente dispares. Por ello, el objetivo de nuestro trabajo es analizar con detalle y en conjunto dichos modelos centrándonos en un grupo con características muy similares. Concr…

Intelligence can be detected but is not found attractive in videos and live interactions

2021

Humans’ extraordinary intelligence seems to extend beyond the needs for survival. One theory to explain this surplus intelligence is that it evolved via sexual selection as a fitness indicator to advertise genetic quality to prospective mates. Consistent with this idea, self-reported mate preferences suggest intelligence is valued across cultures. Yet, as the validity of these self-reports has been questioned, it remains unclear whether objectively assessed intelligence is indeed attractive. We analysed data from two studies to test this key premise of the sexual selection theory of intelligence. In Study 1, 88 target men had their intelligence measured and based on short video clips were r…

Microhabitat selection and audible sexual signalling in the wolf spider Hygrolycosa rubrofasciata (Araneae, Lycosidae)

2000

We studied the microhabitat selection and male sexual signalling behaviour in the wolf spider Hygrolycosa rubrofasciata (Ohlert). Males strike dry leaves with their abdomen, producing an audible sexual drumming signal, and females use this signal to choose mating partners. In the field we followed male drum- ming rate and microhabitat selection using both the mark-recapture method and direct observations. In the laboratory we conducted an experiment on male micro- habitat and drumming substrate selection. We found that in the field males were not distributed randomly among the habitat; fewer males were found in areas that had high sedge cover, low elevation, and low dry leaf cover. In the l…