483 research outputs found
Nonparametric item response theory for investigating dimensionality of marketing scales:A SERVQUAL application
Advances in nonparametric item response theory for scale construction in quality-of-life research
We introduce the special section on nonparametric item response theory (IRT) in Quality of Life Research. Starting from the well-known Rasch model, we provide a brief overview of nonparametric IRT models and discuss the assumptions, the properties, and the investigation of goodness of fit. We provide references to more detailed texts to help readers getting acquainted with nonparametric IRT models. In addition, we show how the rather diverse papers in the special section fit into the nonparametric IRT framework. Finally, we illustrate the application of nonparametric IRT models using data from a questionnaire measuring activity limitations in walking. The real-data example shows the quality of the scale and its constituent items with respect to dimensionality, local independence, monotonicity, and invariant item ordering
A multi‐scale approach to rural depopulation in Mexico
This paper aims to sketch rural population decline in Mexico. A comprehensive multi-scale documentation of Mexico's urban and rural fabric and its depopulation dynamics is undertaken. This paper does not identify the causes and effects of rural depopulation, but aims to detect its geographical presence in a manner which other approaches are unable to do. The granularity of rural depopulation is identified as manifested at four different scales: national, state, municipal, and local village scale. We use census data for the period 2000–2010. We relate rural depopulation to spatio-geographical features found in the literature; the relationship of depopulating territories with urban ones and the altitude range in which they are located. We find that proximity to and remoteness from urban areas as well as that of altitude do not follow the typical patterns often observed elsewhere. Unlike that shown in other countries, in Mexico, rural depopulation is manifested mostly in lower-lying areas and despite the fact that most of the country is at altitude. Rural depopulation and disappearance occur mainly in the areas of plains below 1,000 metres above sea level, regardless of the population density of the territories where they were located. Also, our multi-scaling approach has allowed us to identify not just at what scale the phenomenon of rural depopulation is observed, but also, to identify the areas in which the phenomenon is manifested regionally or locally. As we see, much of the phenomenon is concentrated in different areas to what national narratives suggest
Platform Groene grondstoffen, werkgroep 1: duurzame productie en ontwikkeling van biomassa, deelpad: Aquatische biomassa
Het deelpad Aquatische Biomassa heeft een sterke internationale dimensie. Wereldwijd bestaat een groeiende belangstelling voor het aquatisch milieu (denk hierbij aan waterplanten, zoutwaterlandbouw, micro-algen en zeewieren) als leverancier van voedsel, grondstoffen en energie. Daarnaast is er grote aandacht voor watermanagement, met name gezien de problemen die zich aandienen t.a.v. de berging van regenwater en de beschikbaarheid van zoet water voor drinkwatervoorziening en de landbouw. In dit deelpad worden beide thema’s aan elkaar gekoppeld, zodat meerwaarde ontstaat voor duurzame ontwikkeling met een grote internationale uitstraling van biomassa voor grondstof- en energievoorzienin
Social Contexts, Momentary Mood and Affective Variability in Early Adolescence: An Exploratory Ecological Momentary Assessment Study
The frequency, intensity and variability of emotional experiences increase in early adolescence, which may be partly due to adolescents’ heightened affective sensitivity to social stimuli. While this increased variability is likely intrinsic to adolescent development, greater mood variability is nevertheless associated with the risk of internalising psychopathology. Early adolescents (N = 58, ages 13–14) reported their social context and mood when prompted by a smartphone application. Valence, arousal, and their variability were compared across social contexts using multilevel regression models. Social contexts were defined by the presence of close others, peripheral others, both, or neither. Arousal was lower when alone. Valence was lower and more variable, and arousal was more variable when alone than in either close or peripheral company. This is the first time that level and variability of valence and arousal in adolescent affect have been shown systematically to differ for the same individual in different daily-life social contexts
Learning whom not to trust across early and middle adolescence: A longitudinal neuroimaging study to trusting behavior involving an uncooperative other
Longitudinal changes in trusting behavior across adolescence and their neural correlates were examined. Neural regions of interest (ROIs) included the medial prefrontal cortex (mPFC), dorsal anterior cingulate cortex (dACC), left anterior insula (AI), bilateral ventral striatum (VS), and right dorsal striatum (DS). Participants (wave 1 age: M = 12.90) played the investor in a Trust Game with an uncooperative trustee three times (1-year interval). Analyses included 77 primarily Dutch participants (33 females). Participants decreased their investments with wave. Furthermore, activity was heightened in mPFC, dACC, and DS during investment and repayment, and in right VS (investment) and AI (repayment). Finally, DS activity during repayment increased with wave. These findings highlight early–middle adolescence as an important period for developing sensitivity to uncooperative behavior
A Few Close Friends?: Adolescent Friendships’ Effect on Internalizing Symptoms Is Serially Mediated by Desire for More Friends and Social Goal Orientation
Interpersonal connection is a fundamental human motivation, and the extent to which it is fulfilled is a strong predictor of symptoms of internalizing disorders such as social anxiety and depression, perhaps especially during the “social reorienting” period of adolescence. However, little is known about the contribution to this effect of the individual’s social motivations, which are intensified during adolescence. Furthermore, social goal orientation – an individual’s priorities and intentions in social interactions – is an important predictor of vulnerability to internalizing symptoms. Adolescents spend most of their waking lives in classrooms, bounded social networks with a limited pool of candidates for befriending. This study investigated whether friendships within one’s class protects against internalizing symptoms in part by reducing the desire for more classmate friendships, which may tend to promote maladaptive social goals. Participants were 423 young adolescents (M age = 13.2, sd = 0.52 years; 49.4% girls). As predicted, adolescents’ number of reciprocated classroom friendships had a protective effect on internalizing symptoms which was serially mediated by desire for more such friendships, and social goal orientation. However, only demonstration-avoidance goals significantly predicted internalizing symptoms. Unreciprocated friendship nominations were unexpectedly associated with stronger desire and more social anxiety symptoms. The results suggest that the effect of number of friends is mediated by the individual’s thoughts and feelings about their number of friendships, such that a strong desire for more friendships promotes maladaptive goals, oriented toward social status and consequently less oriented toward the cultivation of interpersonal intimacy with the friends they already have
The Effect of Relative Pubertal Maturation and Perceived Popularity on Symptoms of Depression and Social Anxiety in Adolescent Boys and Girls
Research has shown that adolescents – particularly girls – who mature relatively early often experience more internalizing problems. This effect is thought to be partially driven by psychosocial mechanisms, but previous research based relative pubertal maturation on complete samples or population standards, instead of considering the adolescents’ direct peer environment. In the current study the level of adolescents’ pubertal development was assessed relative to their classmates in order to examine relative pubertal maturation. The effects of adolescents’ relative pubertal status, and their perceived popularity, on symptoms of social anxiety and depression in adolescents were studied. All analyses were also performed for absolute pubertal maturation. Participants were 397 young adolescents (M age = 13.06, SD = 0.36, 49.9% girls) at timepoint 1, and 307 (Mage = 14.08, SD = 0.36, 50.5% girls) at timepoint 2. A significant positive relationship was found between relative pubertal timing and symptoms of depression for girls but not boys. Social anxiety symptoms were not significantly related to relative pubertal timing in either sex. Relative pubertal maturation had no effect on change in or persistence of depressive and social anxiety symptoms one year later. The effects of the comparison with the immediate peer environment, did not seem to explain more variance in internalizing symptoms than the effects of early maturation
The factor structure of the Forms of Self-Criticising/Attacking & Self-Reassuring Scale in thirteen distinct populations
There is considerable evidence that self-criticism plays a major role in the vulnerability to and recovery from psychopathology. Methods to measure this process, and its change over time, are therefore important for research in psychopathology and well-being. This study examined the factor structure of a widely used measure, the Forms of Self-Criticising/Attacking & Self-Reassuring Scale in thirteen nonclinical samples (N = 7510) from twelve different countries: Australia (N = 319), Canada (N = 383), Switzerland (N = 230), Israel (N = 476), Italy (N = 389), Japan (N = 264), the Netherlands (N = 360), Portugal (N = 764), Slovakia (N = 1326), Taiwan (N = 417), the United Kingdom 1 (N = 1570), the United Kingdom 2 (N = 883), and USA (N = 331). This study used more advanced analyses than prior reports: a bifactor item-response theory model, a two-tier item-response theory model, and a non-parametric item-response theory (Mokken) scale analysis. Although the original three-factor solution for the FSCRS (distinguishing between Inadequate-Self, Hated-Self, and Reassured-Self) had an acceptable fit, two-tier models, with two general factors (Self-criticism and Self-reassurance) demonstrated the best fit across all samples. This study provides preliminary evidence suggesting that this two-factor structure can be used in a range of nonclinical contexts across countries and cultures. Inadequate-Self and Hated-Self might not by distinct factors in nonclinical samples. Future work may benefit from distinguishing between self-correction versus shame-based self-criticism.Peer reviewe
Update of the list of QPS-recommended biological agents intentionally added to food or feed as notified to EFSA 15: suitability of taxonomic units notified to EFSA until September 2021
The qualified presumption of safety (QPS) approach was developed to provide a generic pre-evaluation of the safety of biological agents. The QPS approach is based on an assessment of published data for each agent, with respect to its taxonomic identity, the body of relevant knowledge and safety concerns. Safety concerns are, where possible, confirmed at the species/strain or product level and reflected by ‘qualifications’. The QPS list was updated in relation to the revised taxonomy of the genus Bacillus, to synonyms of yeast species and for the qualifications ‘absence of resistance to antimycotics’ and ‘only for production purposes’. Lactobacillus cellobiosus has been reclassified as Limosilactobacillus fermentum. In the period covered by this statement, no new information was found that would change the status of previously recommended QPS taxonomic units (TU)s. Of the 70 microorganisms notified to EFSA, 64 were not evaluated: 11 filamentous fungi, one oomycete, one Clostridium butyricum, one Enterococcus faecium, five Escherichia coli, one Streptomyces sp., one Bacillus nakamurai and 43 TUs that already had a QPS status. Six notifications, corresponding to six TUs were evaluated: Paenibacillus lentus was reassessed because an update was requested for the current mandate. Enterococcus lactis synonym Enterococcus xinjiangensis, Aurantiochytrium mangrovei synonym Schizochytrium mangrovei, Schizochytrium aggregatum, Chlamydomonas reinhardtii synonym Chlamydomonas smithii and Haematococcus lacustris synonym Haematococcus pluvialis were assessed for the first time. The following TUs were not recommended for QPS status: P. lentus due to a limited body of knowledge, E. lactis synonym E. xinjiangensis due to potential safety concerns, A. mangrovei synonym S. mangrovei, S. aggregatum and C. reinhardtii synonym C. smithii, due to lack of a body of knowledge on its occurrence in the food and feed chain. H. lacustris synonym H. pluvialis is recommended for QPS status with the qualification ‘for production purposes only’
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