3,284 research outputs found
Prima validazione di un questionario sui videogiochi (QVG)
No full textIntroduzione:
L'utilizzo dei videogiochi è ampiamente diffuso nella popolazione giovanile e
spesso tende ad assumere le caratteristiche di dipendenza. Il presente lavoro esamina
la validità di un breve Questionario sul Videogioco (QVG) riguardante l'attrazione,
la dipendenza e l'abilità nel gioco.
Metodo:
Sulla base della letteratura e della struttura del BDI (Beck et al., 1961) è stata
costruita una versione iniziale del QVG costituita da 51 item. La scala è stata
somministrata a 933 adolescenti (m=465; f=468; età 11-22 anni) assieme alla RSE
(Rosenberg, 1965), al QSC (Campbell et al., 1996) ed a una scheda di rilevazione
del tempo dedicato ai videogiochi. Tenendo conto dei i valori di asimmetria e curtosi
inferiori a 1.06, gli item iniziali sono stati ridotti a 17. Per valutare le proprietà
psicometriche, sono state effettuate un'analisi fattoriale esplorativa (EFA) ed una
confermativa (CFA) col metodo della massima verosimiglianza. Sono state inoltre
calcolate le correlazioni bivariate tra QVG, RSE, QSC e tempo settimanale dedicato
ai videogiochi.
Risultati:
L'EFA (N=433) ha messo in luce tre fattori: Attrazione (lO item), Dipendenza (3
item) e Fortuna-Abilità (2 item), che spiegano il 46.59% della varianza totale. Un
item con saturazioni multiple è stato escluso dalle successive analisi. La CFA (N
=500) ha messo in evidenza, nonostante la significatività del chi-quadro (p<.001),
dei soddisfacenti indici di fit (RMSEA=0.076; CFI=0.94, NNFI=0.92, RMR=0.046).
La coerenza interna è apparsa generalmente buona (Scala totale: r =0.831;
Attrazione: r =0.886; Dipendenza: r =0.805) e appena sufficiente per la Fortuna (r
= 0.665). Le correlazioni hanno mostrato relazioni significative dirette tra le scale
del QVG ed il tempo di utilizzo dei videogiochi; tra Scala totale, Fortuna e QSC; tra
Fortuna e RSE.
Conclusioni:
Complessivamente la scala sembra costituire un soddisfacente indicatore di
attrazione per il gioco anche se appare migliorabile, soprattutto nella sottoscala della
Fortuna
A confirmatory factorial analysis of the Athletic Coping Skill Inventory: an Italian contribution
No full textThe assessment of self and collective efficacy in volleyball
No full textSelf–efficacy is defined as belief in one’s capabilities to organize and execute the courses of actions required
to produce given attainments. Perceived Collective efficacy is defined as a group's shared belief in its conjoint
capabilities to organize and execute the courses of action required to produce given levels of attainments
(Bandura, 1997). To evaluate self and collective efficacy in Italian volleyball players at different competitive
levels we have constructed some non-hierarchical scales to assess specific aspects relevant for this sport, as
emotions regulation, approach to training, technical/tactical capabilities and communication. A preliminary
version was administrated to different samples using two_formats of rating scales: an 11-point and a 5-point
Likert scale. Statistical analysis led us to choose the 5-point scale format (Guicciardi, Fadda and Delitala, 2010)
and revealed a factorial structure composed of four dimensions. Based on the results of this study a new
version of the questionnaires was created and it was named VEBS (volleyball efficacy beliefs scales).Efficacy
scales were administered to an élite sample (n=133) along with other psychological tests (TEOSQ, GEQ, BIG
FIVE) to verify the structural validity. The scales showed adequate values of skewness and kurtosis and values
of Cronbach‘s alpha ranging from .69 to .95. Good fit indices emerged in CFA for self-efficacy (÷2=74.4, df=59,
CFI=.97, TLI=.97, RMSEA=.05) confirming the four factors model. In conclusion, the structural validity of
efficacy scales (of VEBS) has been confirmed, as well as their relationships with the task-orientation, cohesion
and some personality traits (energy and openness)
Le abilità mentali nello sport: un’analisi esplorativa delle proprietà psicometriche dell'ACSI-28
No full textThe always increasing attention toward the influence that mental abilities have on performance, has favoured the construction and validation of new instruments specific for the sport settings. The athletic coping skill is the ability of maintain the emotional control in the most difficult moments of competition and it could represent a factor of success in sport.
The aim of this research was to study the psychometric proprieties of the Athletic Coping Skills Inventory (ACSI-28) of Smith, Schutz, Smoll and Ptacek (1995). The questionnaires measure both the athletic coping abilities and different mental skills (for example: Concentration and Confidence). This Italian version of the ACSI-28 was administered during a sport-medical visit to a sample of athletes of different sports, particularly sports team.
An exploratory analysis has been made by principal component method. The results have shown a partial confirmation of the structure to seven dimensions, with a sufficient internal consistence and an adequate ability of discriminate the athletes according to age, gender and level of competition.
The questionnaire has some interesting potentiality that claim for additional confirmation
'Barbara' and 'Daniela': two cultivars for myrtle berries production
No full textFor a long time, many efforts have been done to cultivate myrtle as a possible alternative way to replace collection of berries from spontaneous sources. To promote cultivation, a research program was started in 1995, to study the genetic resources of myrtle and to select cultivars with pigmented fruits. The selection and characterisation of two cultivars 'Barbara' and 'Daniela,' are among others the outcomes of this research project. 'Barbara' can be characterised by shrub habitus, low vigour and medium-high yield. Its vegetation cycle starts in March and the plants grow until November. It shows an early bloom and early ripening of fruit and the plants are quite uniform in fruit maturation. Fruits are oval-shaped and medium-sized. They have a black-bluish peel and a white flesh with anthocyanin gradations. The number of seeds per fruit is medium-low (8.1) and the pulp/seed ratio is medium either (3.19). The cultivar can be propagation with cutting easily. 'Daniela' shows a medium-high vigour, a shrub habitus and satisfactory yield. Its vegetation cycle starts early in the season (February-March) and lasts until November. The length of its blooming period is intermediate and no reflorescence of plants occurs. Its fruits mature quite early, but the fruits are less uniform within the plant. Fruits are round, medium sized and black bluish. The number of seeds per fruit is high (13.7) and the pulp/seed ratio is medium (2.54). The propagation of plants with cuttings may be evaluated by medium aptitude
THE WEIGHT OF EXPECTANCY-VALUE AND ACHIEVEMENT GOALS ON SCIENTIFIC CAREER INTEREST AND MATH ACHIEVEMENT
No full texthe study explored a taxonomy of alternative latent models to understand the weight of expectancy-value and approach-related goal orientations in predicting students' achievement behaviors (scientific career interest and math achievement). A full model where all the factors contribute to explaining the total variance of outcomes and two models in which the contribution of expectancy-value and achievement goals factors was evaluated separately within a structural equation modeling framework. Results, among a sample of 812 Italian high school students (486 males and 326 females, Mage= 18.3), showed that expectancy-value variables explain a substantial portion of math achievement and career interest variance after controlling for the achievement goals. Moreover, when all path coefficients were allowed (full model), global value and its dimensions of opportunity and emotional cost influenced positively student's career aspirations, expectancy resulted the main predictor of math competence, and mastery and performance goals did not show significant effects on the outcomes
Validazione italiana del Self- and Task-Perception Questionnaire per adolescenti in ambito matematico
No full textAll’interno dell’ambito delle teorie dell’aspettativa-valore, il presente studio è volto alla validazione italiana del Il Self ‒ and Task ‒ Perception Questionnaire (STPQ) per adolescenti messo a punto da Eccles e colleghi per la misura dell’aspettativa, del valore soggettivo e della difficoltà percepita per un dato compito in ambito accademico. Lo strumento, composto da 19
item con un formato di risposta a sei punti, ha mostrato in letteratura buone qualità psicometriche e la capacità di predire la prestazione e i comportamenti di scelta di carriera degli studenti. Nel presente studio si è presa in considerazione la motivazione verso l’apprendimento della matematica in un campione di 440 studenti (232 maschi e 208 femmine) frequentanti l’ultimo anno di licei classici e scientifici. Utilizzando un’analisi fattoriale confermativa gli autori hanno dato supporto alla struttura di primo livello a sei fattori (abilità/aspettativa; valore intrinseco/interesse, valore del risultato/importanza, valore estrinseco/utilità, difficoltà del compito, sforzo richiesto) attesa a livello teorico, la quale è risultata invariante per genere. In linea con quanto trovato a livello internazionale, è emersa inoltre una struttura sovra-ordinata in cui cinque dei sei fattori individuati nell’analisi fattoriale di primo livello vengono aggregati in due fattori di ordine superiore (valore soggettivo del compito, difficoltà percepita). Inoltre, si è supportata la validità di costrutto e predittiva della scala. In conclusione, l’STPQ appare essere un valido ed attendibile strumento per la misura dell’aspettativa, del
valore soggettivo e della difficoltà percepita verso la matematica per studenti di scuola superiore.Within the expectancy-value theory framework, the present study provides support for the Italian validation of the Il Self-This instrument, developed by Eccles and colleagues measures expectancy, subjective task values and perceived difficulty in a specific academic domain. The STPQ consists of 19 items on a 6-point response scale; it shows adequate psychometric proprieties and the ability to predict subsequent performance and career decisions of students. In the present study, we examined motivation toward mathematics in a sample of 440 students (232 males and 208 females), attending the final year of high school. Confirmatory factor analyses were performed to provide support for the six first order factonal structure of the instrument (ability/expectancy, intrinsic/interest value, attainment value/importance, extrinsic/utility value, task difficulty, required effort), which resulted invariant over gender. According with previous international studies, the authors found also a second-order factorial structure, where five of the six first order factors are aggregated in two higher-order factors: subjective task value, and perceived task difficulty. Moreover, this study supported construct and predictive validity of the instrument. Finally, the STPQ could be considered a valid and reliable instrument to measure expectancy, value and task difficulty toward math for high school students
Neuroticism as a moderator of direct and mediated relationships between introversion-extraversion and well-being
No full textAmong personality traits, extraversion has received major theoretical and empirical attention as predictor of subjective well-being (SWB), whereas the role of emotional stability-neuroticism has been partially neglected. The present study aims to study the role of neuroticism in the relationship between introversion-extraversion and SWB. In particular, we explored if the trait of neuroticism moderates the relationships between introversion-extraversion and SWB dimensions (Satisfaction with life, Mastery, Vigour, Social Cheerfulness), directly and by mediation of self-esteem. Indeed, previous studies have suggested that self-esteem is positively associated with high extraversion and low neuroticism and that it positively mediates the relationship between SWB and personality traits in adolescents. For this purpose, a sample of high school students (N = 1173) completed the Oxford Happiness Inventory, the Rosenberg Self-Esteem Scale and the Big Five Questionnaire. In a latent variable model, we examined the interaction effects (direct and indirect) of extraversion and neuroticism on SWB dimensions. Our results showed that the nature of differences between introverts and extraverts on SWB could be related to the level of neuroticism in relation to Satisfaction with life. Moreover, self-esteem mediated the relationship between personality traits and SWB. In particular, mediated moderation effect analysis showed that self-esteem mediates completely the relationship between the interaction term (extraversion x neuroticism) and Mastery, and partially the relationship with Satisfaction with life. Moreover, moderated mediation effect analysis showed that high levels of neuroticism moderate the effect of extraversion on Satisfaction with life and Mastery through the mediation of self-esteem. In conclusion, our results suggest that although extraversion has a cardinal role on SWB dimensions related to Vigour and Social Cheerfulness, neuroticism and the mediating role of self-esteem should more properly considered in relation to Satisfaction with life and Mastery
Chemical profile changes during myrtle (Myrtus communis L.) fruit development and ripening
No full textThe chemical composition of fruit belonging to ‘Barbara’ and ‘Daniela’ myrtle cultivars was monitored
during development from fruit-set to an over-ripe stage (July–January), with the aim to identify a reliable
maturity index. Acidity, pH, reducing and total sugars, phenols, tannins, anthocyans, carbon dioxide and
ethylene production rates were monitored over two different year seasons. Titratable acidity decreased
during maturation, with significant differences due to cultivar and year of observation. Reducing sugars
increased in both cultivars approximately sevenfold from fruit set to complete maturation. Total sugar
content increased similarly ranging from 1.43% and 1.41% at fruit set to 8.28% and 7.56% at maturation
for ‘Barbara’ and ‘Daniela’, respectively. Total phenols and tannins occurred at high levels after fruit set
and declined during development. Anthocyans levels increased, in both cultivars, according to a sigmoid
curve. The pattern of respiration rate showed a gradual decline in both cultivars ranging from 365.81
and 396.42mgkg−1 h−1 to 79.98 and 52.27mgkg−1 h−1, respectively for ‘Barbara’ and ‘Daniela’ in 2006. A
peak of variable size was observed in October–November period. Small increases in ethylene production
have been detected during fruit development ranging from 130.57 and 269.14Lkg−1 h−1 measured at
the onset of development to 13.04 and 19.36Lkg−1 h−1 measured at harvest for ‘Barbara’ and ‘Daniela’,
respectively
- …
