Search results for "Statistic"
showing 10 items of 12520 documents
Robustness of asymmetry and coherence of quantum states
2016
Quantum states may exhibit asymmetry with respect to the action of a given group. Such an asymmetry of states can be considered as a resource in applications such as quantum metrology, and it is a concept that encompasses quantum coherence as a special case. We introduce explicitly and study the robustness of asymmetry, a quantifier of asymmetry of states that we prove to have many attractive properties, including efficient numerical computability via semidefinite programming, and an operational interpretation in a channel discrimination context. We also introduce the notion of asymmetry witnesses, whose measurement in a laboratory detects the presence of asymmetry. We prove that properly c…
Analysis of a viscoelastic phase separation model
2020
A new model for viscoelastic phase separation is proposed, based on a systematically derived conservative two-fluid model. Dissipative effects are included by phenomenological viscoelastic terms. By construction, the model is consistent with the second law of thermodynamics, and we study well-posedness of the model, i.e., existence of weak solutions, a weak-strong uniqueness principle, and stability with respect to perturbations, which are proven by means of relative energy estimates. A good qualitative agreement with mesoscopic simulations is observed in numerical tests.
Persistent joblessness and fertility intentions
2019
Background: The vast majority of demographic studies have approached and operationalised the notion of economic uncertainty using snapshot indicators. Hence, the complexity and diversity of individuals' employment careers were largely hidden. We posit that the persistence of joblessness - that is, repeated and close spells of joblessness - represents a crucial marker of economic uncertainty in the realm of fertility (intention) research. Objective: We aim to explore the association between persistent joblessness of both members of the couple and women's fertility intentions among those who entered employment at least once in the last five years. Methods: We develop an index of persistent jo…
Style partycypacji kulturalnej człowieka dorosłego. Walidacja narzędzia pomiarowego
2018
The article presents a measurement tool validation process diagnosing an adult person’s cultural participation styles. Its objective is to describe the obtained results at individual stages of the validation and determine the connection between cultural participation styles and cultural systems presented by sociologists of culture. Consequently, cultural participation style of an adult person is the subject of the research. The pilot studies as well as the actual research have been conducted in Opolskie province. The research sample amounted to 100 respondents, then 400 respondents, respectively. The theoretical construct of Kazimierz Obuchowski describing the objective and subjective stand…
An operatorial approach to stock markets
2009
We propose and discuss some toy models of stock markets using the same operatorial approach adopted in quantum mechanics. Our models are suggested by the discrete nature of the number of shares and of the cash which are exchanged in a real market, and by the existence of conserved quantities, like the total number of shares or some linear combination of cash and shares. The same framework as the one used in the description of a gas of interacting bosons is adopted.
Determinants of Immigration in Europe. The Relevance of Life Expectancy and Environmental Sustainability
2017
This research analyzes the main variables that determine immigration in Europe and includes aspects related to the economy, population, healthcare, and environmental sustainability. The empirical analysis consists of two sets of data: one made up of all EU member states (EU-28) and the other containing countries that form a part of the Eurozone (EU-19), using the Generalized Method of Moments. The sample covers the period between 2000 and 2014, and the data are analyzed separately and comparatively in the most relevant stages during that time (economic prosperity, crisis, and recovery). The most notable results indicate that the variables related to GDP and public debt largely serve to just…
Formal and Informal Institutions as Drivers of Life Satisfaction in European Regions
2021
For several years the attention of economists has focused mostly on income and related issues. This tendency changed during the last decade, when citizen’s well-being became a topic of increasing interest. In that regard, the appearance of new databases providing reliable data on variables such as happiness or life satisfaction spurred the number of empirical contributions. This chapter contributes to this literature by analysing the links between informal, formal institutions and life satisfaction for a wide sample European regions.
The mediating role of optimism in the relations between sense of coherence, subjective and psychological well-being among late adolescents
2015
Abstract The purpose of this study was to examine whether optimism is a mediator between sense of coherence, subjective well-being and psychological well-being among late adolescents. Two hundred and eleven participants completed the Sense of Coherence Scale, the Life Orientation Test-Revised, the Satisfaction With Life Scale, the Positive and Negative Affect Schedule, and the Psychological Well-Being Scale. Results of path analysis revealed both direct and indirect effects of sense of coherence on subjective and psychological well-being measures, suggesting that optimism served as a partial mediator. The mediating role of optimism may be more fully understood within the framework of the se…
Hardiness as a moderator variable between the Big-Five Model and work effort
2015
Abstract The aim of the present study is to analyse hardiness as a moderator variable among personality traits, assessed using the Big-Five or Five Factor Model (FFM) and responses in work effort of workers confronted with stress. Using a multi-occupational sample of 403 subjects, statistically significant correlations between the factors of the FFM and work effort were found, as well as between hardiness and effort, as predicted by the theoretical model. Finally, empirical evidence indicates that hardiness performs a moderating role between the factors of FFM and effort displayed, in the sense that hardiness (understood as a quantitative variable) affects the intensity of the relationship …
Facilitators, teachers, observers, and play partners : Exploring how mothers describe their role in play activities across three communities
2019
The present study explored the perspectives of mothers from three communities regarding their role in play activities with their toddlers. The mothers of two-year-old children from Muenster, Germany (n = 34), Chennai, India (n = 36), and New York City, USA (n = 36), participated in the study. Qualitative content analysis was utilized to analyze the mothers' responses to semi-structured interview questions. Four roles were identified as characterizing the mothers' narratives, namely mothers as facilitators, teachers, play partners, or observers. The goal of facilitator was to support children's autonomy; teachers often described educational learning goals; and play partners and observers hig…