Michel Boivin

Bio: Michel Boivin is an academic researcher from Laval University. The author has contributed to research in topics: Population & Poison control. The author has an hindex of 77, co-authored 384 publications receiving 22104 citations. Previous affiliations of Michel Boivin include École Normale Supérieure & Université du Québec à Montréal.

Physical Aggression During Early Childhood: Trajectories and Predictors

Abstract: Objectives. Physical aggression in children is a major public health problem. Not only is childhood physical aggression a precursor of the physical and mental health problems that will be visited on victims, but also aggressive children themselves are at higher risk of alcohol and drug abuse, accidents, violent crimes, depression, suicide attempts, spouse abuse, and neglectful and abusive parenting. Furthermore, violence commonly results in serious injuries to the perpetrators themselves. Although it is unusual for young children to harm seriously the targets of their physical aggression, studies of physical aggression during infancy indicate that by 17 months of age, the large majority of children are physically aggressive toward siblings, peers, and adults. This study aimed, first, to identify the trajectories of physical aggression during early childhood and, second, to identify antecedents of high levels of physical aggression early in life. Such antecedents could help to understand better the developmental origins of violence later in life and to identify targets for preventive interventions. Methods. A random population sample of 572 families with a 5-month-old newborn was recruited. Assessments of physical aggression frequency were obtained from mothers at 17, 30, and 42 months after birth. Using a semiparametric, mixture model, distinct clusters of physical aggression trajectories were identified. Multivariate logit regression analysis was then used to identify which family and child characteristics, before 5 months of age, predict individuals on a high-level physical aggression trajectory from 17 to 42 months after birth. Results. Three trajectories of physical aggression were identified. The first was composed of children who displayed little or no physical aggression. These individuals were estimated to account for ∼28% of the sample. The largest group, estimated at ∼58% of the sample, followed a rising trajectory of modest aggression. Finally, a group, estimated to comprise ∼14% of the sample, followed a rising trajectory of high physical aggression. Best predictors before or at birth of the high physical aggression trajectory group, controlling for the levels of the other risk factors, were having young siblings (odds ratio [OR]: 4.00; confidence interval [CI]: 2.2–7.4), mothers with high levels of antisocial behavior before the end of high school (OR: 3.1; CI: 1.1–8.6), mothers who started having children early (OR: 3.1; CI: 1.4–6.8), families with low income (OR: 2.6; CI: 1.3–5.2), and mothers who smoked during pregnancy (OR: 2.2; CI: 1.1–4.1). Best predictors at 5 months of age were mothers’ coercive parenting behavior (OR: 2.3; CI: 1.1–4.7) and family dysfunction (OR: 2.2; CI: 1.2–4.1). The OR for a high-aggression trajectory was 10.9 for children whose mother reported both high levels of antisocial behavior and early childbearing. Conclusions. Most children have initiated the use of physical aggression during infancy, and most will learn to use alternatives in the following years before they enter primary school. Humans seem to learn to regulate the use of physical aggression during the preschool years. Those who do not, seem to be at highest risk of serious violent behavior during adolescence and adulthood. Results from the present study indicate that children who are at highest risk of not learning to regulate physical aggression in early childhood have mothers with a history of antisocial behavior during their school years, mothers who start childbearing early and who smoke during pregnancy, and parents who have low income and have serious problems living together. All of these variables are relatively easy to measure during pregnancy. Preventive interventions should target families with high-risk profiles on these variables. Experiments with such programs have shown long-term impacts on child abuse and child antisocial behavior. However, these impacts were not observed in families with physical violence. The problem may be that the prevention programs that were provided did not specifically target the parents’ control over their physical aggression and their skills in teaching their infant not to be physically aggressive. Most intervention programs to prevent youth physical aggression have targeted school-age children. If children normally learn not to be physically aggressive during the preschool years, then one would expect that interventions that target infants who are at high risk of chronic physical aggression would have more of an impact than interventions 5 to 10 years later, when physical aggression has become a way of life.

The power of friendship: protection against an escalating cycle of peer victimization.

Abstract: This study examined 2 aspects of friendship (presence and perceived qualities of a best friend) as moderators of behavioral antecedents and outcomes of peer victimization. A total of 393 children (188 boys and 205 girls) in the 4th and 5th grades (mean age = 10 years 7 months) participated during each of 2 waves of data collection in this 1-year longitudinal study. Results indicated that teacher-reported internalizing and externalizing behaviors predicted increases in peer-reported victimization, but the relation of internalizing behaviors to increases in victimization was attenuated for children with a protective friendship. Victimization predicted increases in internalizing and externalizing behaviors but only for children without a mutual best friendship. Results highlight the importance of peer friendships in preventing an escalating cycle of peer abuse.

Measuring Friendship Quality During Pre- and Early Adolescence: The Development and Psychometric Properties of the Friendship Qualities Scale:

Abstract: The Friendship Qualities Scale is a theoretically grounded, multidimensional measurement instrument to assess the quality of children's and early adolescents' relationships with their best friends according to five conceptually meaningful aspects of the friendship relation. These dimensions are companionship, conflict, help/aid, security and closeness. A confirmatory factor analysis, used to evaluate the factor structure of this instrument, demonstrated that these scales represented distinct, but related, domains of friendship. Assessments of reliability indicated the high level of internal consistency within each dimension. The validity of the scale was indicated by the observation of higher ratings for (a) mutual friends than for non-mutual friends, and (b) for stable friends than for non-stable friends. These findings are discussed according to the theoretical and practical issues related to the measurement of friendship quality.

Physical aggression during early childhood: trajectories and predictors

Abstract: Introduction: This study aimed to identify the trajectories of physical aggression during early childhood and antecedents of high levels of physical aggression early in life Methods: 572 families with a 5-month-old newborn were recruited Assessments of physical aggression frequency were obtained from mothers at 17, 30, and 42 months after birth Using a semiparametric mixture model and multivariate logit regression analyses, distinct clusters of physical aggression trajectories were identified, as well as family and child characteristics that predict high level aggression trajectories Results: Three trajectories of physical aggression were identified: 1 children (28% of sample) who displayed little or no physical aggression, 2 approximately 58% followed a rising trajectory of modest aggression, and 3 a rising trajectory of high physical aggression (14%) Conclusions: Children who are at highest risk of not learning to regulate physical aggression in early childhood have mothers with a history of antisocial behaviour during their school years, mothers who start childbearing early and who smoke during pregnancy, and parents who have low income and have serious problems living together Preventive interventions should target families with high-risk profiles on these variables Language: en

Academic Self-Concept and Academic Achievement: Developmental Perspectives on Their Causal Ordering.

Abstract: This study tests theoretical and developmental models of the causal ordering between academic self-concept and academic achievement in a multicohort-multioccasion design (i.e., 3 age cohorts, each with 3 measurement waves). Participants were students in Grades 2, 3, and 4 from 10 elementary schools. The structural equation model for the total sample supported a reciprocal-effects model, indicating that achievement has an effect on self-concept (skill-development model) and that academic self-concept has an effect on achievement (self-enhancement model). This pattern was replicated in tests of invariance across the 3 age cohorts and did not support the developmental hypothesis that skill-development and self-enhancement models would vary with age. Discussion centers on the theoretical, methodological, and practical implications of the results. (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Using Multivariate Statistics

Abstract: Thank you for downloading using multivariate statistics. As you may know, people have look hundreds times for their favorite novels like this using multivariate statistics, but end up in infectious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they juggled with some harmful bugs inside their laptop. using multivariate statistics is available in our digital library an online access to it is set as public so you can download it instantly. Our books collection saves in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the using multivariate statistics is universally compatible with any devices to read.

Human biochemical genetics

Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Multiple Imputation for Nonresponse in Surveys

Abstract: 25. Multiple Imputation for Nonresponse in Surveys. By D. B. Rubin. ISBN 0 471 08705 X. Wiley, Chichester, 1987. 258 pp. £30.25.