Prediction of university students' academic achievement by linear and logistic models

University students' academic achievement measured by means of academic progress is modeled through linear and logistic regression, employing prior achievement and demographic factors as predictors. The main aim of the present paper is to compare results yielded by both statistical procedures, in order to identify the most suitable approach in terms of goodness of fit and predictive power. Grades awarded in basic scientific courses and demographic variables were entered into the models at the first step. Two hypotheses are proposed: (a) Grades in basic courses as well as demographic factors are directly related to academic progress, and (b) Logistic regression is more appropriate than linear regression due to its higher predictive power. Results partially confirm the first prediction, as grades are positively related to progress. However, not all demographic factors considered proved to be good predictors. With regard to the second hypothesis, logistic regression was shown to be a better approach than linear regression, yielding more stable estimates with regard to the presence of ill-fitting patterns.     

Reputation, loneliness, satisfaction with life and aggressive behavior in adolescence

The present study analyses the relationship between adolescents' perception of reputation and aggressive behavior among peers. The sample is made up of 1319 adolescents aged 11 to 16-years-old. Statistical analyses with structural equation modeling were carried out to examine the direct and indirect effect of perception of reputation (real and ideal) on aggressive behavior. Results indicate that adolescents' real and ideal reputations are related both directly and indirectly to aggressive behavior. The indirect effects suggest that loneliness and life satisfaction mediate the relationship between adolescents' reputation and their aggressive behavior. These findings and their implications are discussed.     

Maternal concepts and expectations regarding a preterm infant

The objective of the present study was: (a) to identify the concerns, verbally expressed, of 50 mothers regarding their preterm infants (PT) and then compare their verbal expression with those of 25 mothers of full-term infants (FT); and (b) to correlate the mothers' verbal expressions with maternal and infant variables. The following instruments were used to compose and characterize the sample: Structure Clinical Interview for DSM III-R Non-Patient (SCID/NP), State-Trait Anxiety Inventory (STAI), Beck Depression Inventory (BDI), and medical charts. Results showed that there was no difference between groups in term of mothers' expectations and conceptualizations; both groups exhibited predominantly positive expectations and concepts. In comparison with FT mothers, PT mothers verbally expressed more feelings and reactions predominantly negative or conflicting in relation to infant birth. Higher levels of maternal anxiety and depression in the PT Group were correlated with more verbal expressions about negative or conflicting emotions. In addition, lower birth weight, higher neonatal risk and longer length of stay in intensive care nursery of the infants were related with more negative or conflicting concepts by the mothers.     

A comparison of the peers method and traditional methodologies, and risk behaviors in studies of the prevalence of drug consumption in a population of female, Chilean students

The present study investigates drug consumption and risk behaviors among female students between 8th and 12th grade in two communities in the city of Santiago, Chile. Based on studies of university populations, we hypothesize that the students' reports of their consumption of licit drugs will tend to be consistent with their actual use of said drugs using two methods to investigate consumption, while their consumption of illicit drugs will be susceptible, and will tend to be under-reported when evaluated through traditional self-report measures. In order to compare the two methods, a cross-sectional study was designed that would compare reported drug consumption, first using the peers method, and then by means of traditional self-report in a group of 350 students. The results show that women's reports of licit drug consumption converge using the two methods, while as earlier suggested, women's illicit drug consumption was found to be under-reported when traditional methodologies were used.     

Comparison of single- and double-stage designs in the prevalence estimation of eating disorders in community samples

The aim of this research was to compare two different case-identification designs: (a) a one-stage anonymous design using the Eating Disorders Examination-Questionnaire (EDE-Q; Fairburn & Beglin, 1994) as diagnostic instrument and (b) a two-stage-non-anonymous design using the Eating Attitudes Test (EAT; Garner & Garfinkel, 1979) and the EDE-Q as screening instruments and the clinical interview Eating Disorders Examination (EDE; Fairbumrn & Cooper, 1993) as diagnostic instrument, in the estimation of eating disorders prevalence in community samples. Both epidemiological designs were compared in: eating disorders prevalence, population at risk, and weekly frequency of associated symptomatology (binge eating episodes, self-vomiting) within a sample of 559 scholars (14 to 18 year-old males and females) studying in the region of Madrid. Eating disorders prevalence estimation using single-stage design was 6.2%, and 3% using the two-stage design; however, these differences were not significant (p = .067). No significant differences between the two procedures were found either in population at risk or in weekly frequency of reported self-vomiting. Reported binge eating episodes were higher in the one-stage design. The use of a two-stage procedure with clinical interview (vs. questionnaire) leads to a better understanding of the items (specially the most ambiguous ones) and thus, to a more accurate prevalence estimation.     

Implicit orientation toward family and school among bilingual Latino college students

The authors examined the associations that underlie the orientations of bilingual Latino college students toward family and school. Participants completed, in English or Spanish, 3 implicit association tests assessing their attitude toward family vs. school, identifications with these concepts, and self-esteem. Results revealed a more positive attitude toward, and stronger identification with, family than school. Identification with family was stronger among participants who completed the study in English, suggesting self-definition in terms of distinctions from the context. Last, the more participants valued family over school and identified with family rather than school, the higher was their self-esteem. These findings shed light on the subtle, yet crucial, mechanisms by which cultural knowledge is incorporated in the self-concept of bilingual Latino college students.     

Analysis of effects of distribution of practice in learning and retention of a continuous and a discrete skill presented on a computer

This investigation examined the effects of distributed and massed practice on the learning and retention of a discrete computerized skill (Exp. 1) and a continuous computerized skill (Exp. 2). 40 men were randomly assigned to one of four groups, of which two groups took part in Exp. 1 and two groups in Exp. 2. Performance was assessed at various points during acquisition and then on 8 retention tests conducted at varying times after acquisition. Learning curves for practice were highly similar for the two conditions. Participants in the distributed-practice group performed significantly better than those in the massed-practice group at the end of practice on both the discrete and continuous skills. However, participants in the distributed-practice group performed significantly more poorly on retention during 24 hr. and after acquisition. Participants in the massed-practice condition performed significantly better on retention tests than did those who learned in the distributed-practice condition.     

Influence of articulation rate on two memory tasks in young and older adults

This study investigated the relation between phonological loop functioning and age. Phonological loop is a time-based subsystem of the Working Memory Model of Baddeley and Wilson, which uses rehearsal of information as an active process to avoid phonological decay. Performance differences were examined between young and older adults in two speech-based memory tasks, such as the immediate serial recall of words and the Digit Ordering Task. Analysis showed that performance on both tasks was lower for the older group. Articulation rate was also measured to test the hypothesis that the impairment of some cognitive functions in adults can be associated to their slowness or the greater time needed by older adults for the rehearsal process. A significant negative correlation was found for articulation rate with age. When the effect of articulation rate on Serial Recall and Digit Ordering Tasks was partialled out, the difference between the two groups was eliminated.     

Structure and conventions

Wayne Davis’s Meaning, Expression and Thought argues that linguistic meaning is conventional use to express ideas. An obvious problem with this proposal is that complex expressions that have never been used are nonetheless meaningful. In response to this concern, Davis associates conventions of use not only with linguistic expressions but also with the modes in which such expressions can combine into larger expressions. I argue that such constructive conventions are in conflict with the principle of compositionality (as it is usually understood) and that (at least in the cases Davis considers) they are unnecessary for semantic explanations.