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Estimação de parâmetros genéticos para características de crescimento em bovinos da raça Canchim com modelos de dimensão finita e infinitaBaldi Rey, Fernando Sebastián [UNESP] 26 September 2008 (has links) (PDF)
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baldirey_fs_dr_jabo.pdf: 751142 bytes, checksum: 4a3bdaf84424f12abb37e90cff761fdc (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Foram estimados parâmetros genéticos para pesos do nascimento à idade adulta de animais da raça Canchim por meio de análises uni, bi e multicaracterística, e por modelos de regressão aleatória. Os dados analisados são provenientes do rebanho da raça Canchim da Embrapa Pecuária Sudeste, localizada no município de São Carlos, São Paulo. Os pesos foram obtidos do nascimento até os nove anos e meio de idade. Nas análises uni, bi e multicaracterística foram utilizados pesos em ao nascimento, desmama, 12, 18, 24 e 30 meses de idade e, na idade adulta. Na análise unicaracterística foram utilizados quatro modelos, em que, diferentes efeitos aleatórios (efeito genético materno e de ambiente permanente materno) foram adicionados em seqüência. Nas análises de regressão aleatória, foram utilizados pesos de fêmeas do nascimento até os nove anos e meio de idade, considerando como funções base polinômios de Legendre e funções “b-splines”. A variância residual foi modelada utilizando 1, 4, 11 e 19 classes. Foram utilizados 12 modelos de regressão aleatória sobre polinômios de Legendre de segunda à sétima ordem para modelar a trajetória da variância dos efeitos genético aditivo direto e aditivo materno e de ambiente permanente direto e materno. Vinte modelos de regressão aleatória sobre funções “bsplines” foram considerados, empregando polinômios linear, quadrático e cúbico para cada segmento individual. Polinômios do mesmo grau foram considerados no modelo para todos os efeitos aleatórios. Até sete segmentos foram utilizados para os efeitos genético direto e de ambiente permanente do animal. Para os efeitos genético aditivo materno e de ambiente permanente materno foi utilizado um único segmento com dois nós nos extremos da curva Os efeitos maternos influenciam os pesos do nascimento aos dois anos de idade sendo o peso à desmama... / Genetic parameters were estimated for weights taken from birth to mature age in Canchim (5/8 Charolais + 3/8 Zebu) cattle of breed by one, two and multitrait analyses and by random regression models. The data analyzed were from a herd of Canchim beef cattle belonging to Embrapa’s Southeast Cattle Research Center, located in São Carlos county, state of São Paulo. Weights were taken from birth to nine and half years of age. Weights at birth, weaning, 12, 18, 24 and 30 months of age and at mature age were analyzed using one, two and multitrait models. In onetrait analyses, four models were tested, in which different random effects (genetic and environment permanent maternal effects) were added. For random regression models age of cow varied from birth to 3.542 days of age. Legendre polynomials and b-splines functions of age at recording were used as basis functions in random regression models. Residual variances were modeled by a step function with 1, 4, 11 and 19 classes. A total of 12 random regression models using Legendre polynomials as basis functions, from second to seventh order, were used to model direct and maternal genetic effects, animal and maternal permanent environmental effects. A total of twenty analyses, considering linear, quadratic and cubic b-splines functions and up to nine knots, were carried out. Spline functions of the same order were considered for all random effects. Maternal effects influenced weights from birth until two years of age, being weaning weight the most affected by maternal effects. Direct heritabilities obtained by twotrait and multitrait analyses were higher than estimates obtained from onetrait analyses. In order to estimate genetic parameters for weights after selection it is important to consider weights before selection and the multitrait analyses is the most adequate. The model with direct and maternal genetic effects, animal and maternal... (Complete abstract click electronic access below)
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Model Criticism for Growth Curve Models via Posterior Predictive Model CheckingJanuary 2015 (has links)
abstract: Although models for describing longitudinal data have become increasingly sophisticated, the criticism of even foundational growth curve models remains challenging. The challenge arises from the need to disentangle data-model misfit at multiple and interrelated levels of analysis. Using posterior predictive model checking (PPMC)—a popular Bayesian framework for model criticism—the performance of several discrepancy functions was investigated in a Monte Carlo simulation study. The discrepancy functions of interest included two types of conditional concordance correlation (CCC) functions, two types of R2 functions, two types of standardized generalized dimensionality discrepancy (SGDDM) functions, the likelihood ratio (LR), and the likelihood ratio difference test (LRT). Key outcomes included effect sizes of the design factors on the realized values of discrepancy functions, distributions of posterior predictive p-values (PPP-values), and the proportion of extreme PPP-values.
In terms of the realized values, the behavior of the CCC and R2 functions were generally consistent with prior research. However, as diagnostics, these functions were extremely conservative even when some aspect of the data was unaccounted for. In contrast, the conditional SGDDM (SGDDMC), LR, and LRT were generally sensitive to the underspecifications investigated in this work on all outcomes considered. Although the proportions of extreme PPP-values for these functions tended to increase in null situations for non-normal data, this behavior may have reflected the true misfit that resulted from the specification of normal prior distributions. Importantly, the LR and the SGDDMC to a greater extent exhibited some potential for untangling the sources of data-model misfit. Owing to connections of growth curve models to the more fundamental frameworks of multilevel modeling, structural equation models with a mean structure, and Bayesian hierarchical models, the results of the current work may have broader implications that warrant further research. / Dissertation/Thesis / Doctoral Dissertation Educational Psychology 2015
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Desempenho zootécnico de tambaquis (Colossoma macropomum, Cuvier 1818) da primeira geração de seleção genética para ganho de pesoMarcos, Rebeca 19 February 2014 (has links)
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Previous issue date: 2014-02-19 / CAPES / Objetivou-se acompanhar o desempenho zootécnico, as características morfométricas e analisar o padrão de crescimento dos tambaquis da primeira geração de seleção genética para ganho de peso. O trabalho foi realizado no período de setembro de 2012 a maio de 2013 no município de Santo Antônio de Leverger – Mato Grosso, Brasil. Foram estudadas sete famílias oriundas do programa de melhoramento genético e um grupo controle (sem melhoramento). Todos os animais foram individualizados com microchips. Foram avaliadas e mensuradas as seguintes características: ganho de peso, comprimento total, comprimento padrão, tamanho de cabeça, altura, largura e perímetro do corpo. O experimento seguiu um delineamento inteiramente casualizado e foram avaliados dados coletados durante nove biometrias mensais dos grupos de tambaqui melhorados geneticamente e o controle (sem melhoramento). Para descrever o desempenho zootécnico dos tambaquis, as comparações entre os tratamentos (famílias e controle) usou-se o teste de Dunnett com 5% de significância e para o comportamento do crescimento dos tambaquis utilizou-se o modelo matemático de regressão não linear de Gompertz. Cinco das sete famílias avaliadas (A, B, D, E e G) apresentaram maior peso final, ganho de peso diário e crescimento morfométrico quando comparada ao controle (sem melhoramento). Apenas a família C do programa de melhoramento genético apresentou peso final, ganho de peso diário e as características morfométricas inferiores em relação ao controle (sem melhoramento) e a família F apresentou resultados semelhantes ao controle (sem melhoramento). Os animais melhorados geneticamente apresentaram padrão de crescimento diferente e superior em relação aos animais não melhorados (grupo controle), em se tratando, principalmente do peso assintótico. / Aimed to monitor the production performance, morphometric characteristics and analyze the growth pattern of tambaquis the first generation of genetic selection for weight gain. The study was conducted from September 2012 to May 2013, in Santo Antônio de Leverger - Mato Grosso, Brazil. Seven families from the breeding program and a control group (no improvement) were studied. All animals were individually microchipped. Were evaluated and measured the following characteristics: weight gain, total length, standard length, head size, height, width and perimeter of the body. The experiment followed a completely randomized design and data collected for nine monthly biometrics groups of genetically improved tambaqui and control (no improvement) were evaluated. To describe the production performance of tambaquis, comparisons between treatments (families and control) we used the Dunnett test with 5% significance and the growth behavior of tambaquis used the nonlinear mathematical model of Gompertz regression. Five out of seven families (A, B, D, E and G) had higher final weight, average daily gain and morphometric growth compared to the control (no improvement). Only the C family breeding program presented final weight, average daily gain and lower morphometric characteristics compared to the control (no improvement) and F family presented similar to the control (no improvement) results. Genetically improved animals showed different pattern of growth and higher compared to unimproved animals (control group), in the case, especially the asymptotic weight.
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Estudo biológico de linhagens do protozoário ciliado Paramecium Caudatum Ehrenberg, 1833 e avaliação experimental do efeito tóxico do agrotóxico FipronilAlves, Henrique Cezar 26 November 2010 (has links)
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Previous issue date: 2010-11-26 / Universidade Federal de Minas Gerais / Protozoans has been proposed as biological indicators of water pollution due to their sensitivity to environmental changes, their short life cycle and easy cultivation, this work intended to study two strains of the ciliated protozoan Paramecium caudatum Ehrenberg, 1833 (PC1 isolated from the Monjolinho Reservoir - São Carlos-SP and maintained in monoxenic culture at the Laboratory of Ecology of Aquatic Microorganisms of UFSCar and PC2 isolated from Óleo Lagoon an oxbow lake in the Moji-Guaçu River floodplain Luiz Antônio- SP). Experiments were done aiming to study the life cycle, best cultivation conditions and to verify the toxicity of the pesticide fipronil to these protozoan lineages, considering that the local from which they were isolated have differing history of contamination with the pesticide. The experiments were executed aiming to verify the possibility of the utilization of these organisms as environmental bioindicators in a standardized bioassay. The best culture condition obtained for PC1 was at pH 9 and 30 °C and for PC2 was at pH 7 and 27.5 °C. For the two lineages the best results were obtained with no light and agitation and the increase of the cultivation scale not interfered significantly in the growth. It was possible to observe that in culture, the PC2 has a slower growth and, in the other hand higher densities than PC1. Compared with other organisms, the two lineages are very resistant to fipronil, and as a result not suitable as bioindicators of environmental contamination by this pesticide. Besides, because they are food items for the higher trophic levels, their resistance to the pesticide led us to consider that in the contaminated ecossystems, these organisms can be important for the fipronil accumulation in the food web. However, the studied ciliates displayed potential to be used as test-organisms for ecotoxicological assays. / Protozoários têm sido propostos como indicadores biológicos de poluição aquática devido à sua sensibilidade a alterações ambientais, ao seu curto ciclo de vida e facilidade para cultivo, o presente trabalho pretendeu estudar duas linhagens do protozoário ciliado Paramecium caudatum Ehrenberg, 1833 (PC1, isolada da Represa do Monjolinho - São Carlos-SP e mantida em cultura monoxênica no Laboratório de Ecologia de Microrganismos Aquáticos da UFSCar e outra, a PC2, que foi isolada da Lagoa do Óleo-Lagoa marginal do Rio Moji- Guaçu- SP). Foram feitos experimentos que tiveram por objetivo estudar o ciclo de vida, obter as melhores condições de cultivo e verificar diferenças na sensibilidade dessas duas linhagens ao fipronil considerando que os locais de origem dessas linhagens possuem diferente histórico prévio de exposição ao agrotóxico. Os experimentos executados também visaram verificar a possibilidade de utilização desses organismos como bioindicadores ambientais em bioensaio padronizado. As melhores condições de cultivo para a linhagem PC1 foram em pH 9, a 30°C, e para PC2 foram em pH 7, a 27,5°C, sendo que para as duas linhagens o melhor crescimento foi sem iluminação ou agitação e o aumento na escala do cultivo não interferiu significativamente no crescimento. Em cultura foi possível observar que PC2 apresenta reprodução mais lenta, porém atinge maiores densidades que PC1. A linhagem PC2 é mais sensível ao fipronil. Comparadas a outros organismos, as duas linhagens são bastante resistentes ao fipronil, não sendo interessantes como indicadores de contaminação desse agrotóxico no ambiente. Além disso, por serem alimento de níveis tróficos superiores, a resistência apresentada ao agrotóxico nos leva a crer que nos ecossistemas contaminados, esses organismos podem ser importantes para a acumulação do fipronil na rede alimentar onde estão presentes. Entretanto, os ciliados estudados mostraram ser bons organismos-teste para ensaios ecotoxicológicos.
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Estudo de modelos não-lineares na descrição do crescimento de fêmeas da raça Canchim /Gaviolli, Vanessa Rejane Nogueira. January 2010 (has links)
Resumo: Os objetivos deste trabalho foram identificar as funções matemáticas que melhor se ajustam para descrever o crescimento de fêmeas da raça Canchim e do grupo genético MA (filhos de touros da raça Charolesa e vacas ½ Canchim + ½ Nelore), e estimar a herdabilidade dos parâmetros A e k da curva que melhor se ajustou aos dados e a correlação genética desses com a idade (IPP) e o peso (PPP) ao primeiro parto e idade (ISP) e peso (PSP) ao segundo parto. As funções não lineares Brody, Richards, Von Bertalanffy e duas alternativas de Gompertz e de Logístico foram ajustadas pelo método de Gauss Newton e procedimento NLIN do SAS, a dados peso-idade de 1.923 bovinos da raça Canchim e MA, nascidos de 1972 a 2006, com pesagens no mínimo até os 37 meses de idade e no máximo até os 100 meses de idade e com pelo menos sete pesagens. A comparação entre os modelos foi realizada com base na interpretação biológica dos parâmetros e nos avaliadores de qualidade de ajuste. A estimação dos parâmetros genéticos foi feita pelo método da máxima verossimilhança restrita, utilizando análises uni e bicaracterísticas com modelos que incluíram o efeito fixo de grupo de contemporâneos e o efeito aleatório aditivo direto. Os modelos Brody e Von Bertalanffy ajustaram aos dados peso-idade, enquanto que os demais não convergiram, sendo que o modelo Brody foi escolhido para a obtenção dos parâmetros A e k de cada animal. As estimativas de herdabilidade obtidas foram 0,32 ± 0,05; 0,12 ± 0,04; 0,12 ± 0,04; 0,43 ± 0,06; 0,19 ± 0,06 e 0,44 ± 0,06, para A, k, IPP, PPP, ISP e PSP, respectivamente. Estes resultados sugerem que é possível, mas difícil obter mudanças na curva de crescimento dos animais pela seleção. As estimativas de correlação genética dos parâmetros A e k com as idades e os pesos aos partos sugerem que a seleção para modificar A deve provocar mudanças no ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objectives in this study were to identify the mathematical function that best fits the growth of Canchim and MA (offspring of Charolais bulls and ½ Canchim + ½ Nelore cows) females, and to estimate the heritability of parameters A and k of the function that best fitted the data and the genetic correlations of these parameters with age (IPP) and weight (PPP) at first calving and age (ISP) and weight (PSP) at second calving. Brody, Richards, Von Bertalanffy and two alternatives of Gompertz and of Logistic non-linear models were fitted by Gauss Newton method and NLIN procedure of SAS. Weight-age data of 1,923 females born from 1972 to 2006, with weighing at least at 37 months of age and at most at 100 months of age, and with at least seven weighing were used. The comparison between the models was based on the biological interpretation of parameters and measures of quality of adjustment. The genetic parameters were estimated by the restricted maximum likelihood method using one and two-trait analyses with animal models that included the fixed effect of contemporary group and the random additive direct effect. The Brody and the Von Bertalanffy models adjusted the weight-age data well, while the others did not converge, and the Brody function was chosen to obtain the parameters A and k of each animal. The heritability estimates were 0.32 ± 0.05, 0.12 ± 0.04, 0.12 ± 0.04, 0.43 ± 0.06, 0.19 ± 0.06 and 0.44 ± 0.06 for A, k, IPP, PPP, ISP and PSP were, respectively. These values suggest that it is possible, but difficult to obtain changes in the pattern of the growth curve of the animals by selection. Estimates of genetic correlation of parameters A and k with the other traits suggest that selection to change A should cause changes in the same direction in PPI, PPP, ISP and PSP, and that changes in k, if they occur, should also be followed by changes in the other traits, but in the opposite direction / Orientador: Maurício Mello de Alencar / Coorientador: Alfredo Ribeiro de Freitas / Banca: Danísio Prado Munari / Banca: Lenira El Faro Zadra / Mestre
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Análise de resíduos projetados em modelos não-lineares de regressão: uma aplicação em crescimento de frutos / Residual Analysis designed in non-linear regression: an application to fruit growthMaria Cristina Martins 24 January 2013 (has links)
Alguns aspectos devem ser considerados nos trabalhos com frutíferas como o ponto adequado de colheita e estratégias de conservação, sendo fundamental a análise do crescimento e desenvolvimento dos frutos. Vários tipos de modelos estatísticos podem descrever os processos de crescimento envolvidos no sistema de produção vegetal, sendo os modelos não lineares considerados mais adequados para esse tipo de estudo. Para que os resultados obtidos no ajuste do modelo sejam válidos é necessário verificar a qualidade de ajuste por meio de uma análise dos resíduos. A distribuição dos resíduos ordinários para os modelos de regressão não linear, é matematicamente trabalhosa e os critérios de diagnóstico são falhos, principalmente em pequenas amostras. Diante de tal fato, Cook e Tsai (1985) definiram o resíduo projetado. O comportamento dos resíduos projetados é melhor do que o dos resíduos ordinários, pois suas propriedades são mais próximas das correspondentes ao resíduo ordinário da regressão normal linear. O ganho é substancial se o teste para a medida de não linearidade for significativo. Por meio dos ajustes dos modelos logístico e de Gompertz aos dados de comprimento de peras foi realizada a análise dos resíduos ordinários e dos resíduos projetados, a fim de evidenciar suas vantagens. Os resíduos projetados se mostraram viáveis para diagnóstico dos modelos e descartaram possíveis tendências apresentadas pelos resíduos normalizados. / Some aspects must be considered in the works with fruit tree such as the appropriate point of harvest and conservation strategies, being fundamental the analysis of growth and fruit developments. Several types of statistical models can describe the growth processes involved in plant production system and the non-linear models are considered more suitable for this type of study. For the results obtained from the model fit to be valid is necessary to check the quality of fit through a residual analysis. The distribution of the ordinary residuals in the non-linear regression models is mathematically complicated and the diagnostic criteria are not precise, mainly in small samples. To overcome this fact, Cook and Tsai (1985) defined the projected residual. The behaviour of the projected residuals is better than the ordinary residuals since their properties are closer to those corresponding to the ordinary residuals for the normal linear regression. The gain is substantial if the test for non-linearity is significant. Through the fit of the logistic and Gompertz models to the pears length data, it was performed an analysis of the ordinary and projected residuals in order to demonstrate their advantages. The projected residuals showed more feasible for the diagnostic of the models and ruled out possible trends presented by normalized residuals.
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BVC-sjuksköterskans upplevelse av mötet med överviktiga barn och deras föräldrar : En kvalitativ studie / The child health nurse's experience of meeting with overweight children and their parents : A qualitative studyAndersson, Lena, Morsten, Johanna January 2019 (has links)
Övervikt och fetma ökar bland barn i Sverige. Under de senaste 25 åren har fetmaförekomsten hos barn ökat från 1 procent till 4 procent. Totalt bland barn i Sverige idag lider 15–20 procent av övervikt och fetma. Studier har visat att 80 procent av de som lider av övervikt under förskoleåldern även lider av övervikt när de lämnar tonåren. Barn med fetma kan utveckla insulinresistens, blodfettrubbningar, påverkan på levern, psykisk ohälsa, och är en av dem främsta orsakerna till förlorade friska levnadsår. Det är därför viktigt att förebygga barnfetma och sätta in behandling tidigt. Barnhälsovårdssjuksköterskan har en unik roll att kunna påverka föräldrar och barn, tidigt i livet. Mötet mellan BVC-sjuksköterskan och familjen måste bli bra för att få rätt förutsättningar att kunna påverka. Syftet med studien är att beskriva BVC-sjuksköterskans upplevelse av mötet med överviktiga barn och deras föräldrar. För att få svar på forskningsfrågan gjordes en kvalitativ innehållsanalys med en induktiv inriktning efter att sju BVC-sjuksköterskor intervjuats kring sina erfarenheter. Intervjumaterialet resulterade i fem kategorier: Första mötet – en god start, att tydliggöra övervikt, BVC-sjuksköterskans begränsningar, mötet med familjens värld och det långsiktiga arbetet. I resultatet framkom att BVC-sjuksköterskans första möte med det överviktiga barnet och hens föräldrar är mycket viktigt, men att BVC-sjuksköterskorna känner att de saknar specifik utbildning för detta möte. BVC-sjuksköterskorna använde sig av både iso-BMI och tillväxtkurvan i sitt arbete, men föredrog att använda tillväxtkurvan framför iso-BMI. Diskussionen tar upp vikten av att ta tag i problemet med övervikt i ett tidigt skede i livet för att minska framtida vårdkostnader och ett lidande för barnet upp i vuxen ålder. / Overweight and obesity are increasing among children in Sweden Over the past 25 years the incidence of obesity in children has increased from 1 percent to 4 percent. A total of 15–20 percent of children in Sweden suffer from overweight or obesity. Studies have shown that 80 percent of those who suffer from overweight during preschool age also suffer from overweight when leaving adolescence. Children with obesity can develop insulin resistance, blood fat disorders, liver effects, mental illness. Obesity is one of the leading causes of loss of healthy years of life. It is therefore important to prevent childhood obesity and start treatment early. The child health care nurse has a unique role in being able to influence parents and children early in life. And the meeting between the child health care nurse and the family must be sufficient in order to have the right conditions to be able to influence. The purpose of this study is to describe the child health care nurse's experience of meeting overweight children and their parents. To obtain answers to the research question, a qualitative content analysis was conducted with an inductive focus in which seven child health care nurses were interviewed about their experiences. The interview material resulted in five categories: The first meeting - a good start, clarifying obesity, the child care nurses limitations, meeting the family's world and the long-term work. The results showed that the child health care nurse's first meeting with the overweight children and their parents is very important, but also that the health care nurses felt that they lacked specific education for this meeting. The child health care nurses used both iso-BMI and the growth curve, but preferred to use the growth curve over iso-BMI. The discussion addresses the importance of the child health care nurse work to prevent the problem of being overweight at an early stage in life to reduce future health care costs and suffering for the child even when becoming adult.
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The unweighted mean estimator in a Growth Curve modelKarlsson, Emil January 2016 (has links)
The field of statistics is becoming increasingly more important as the amount of data in the world grows. This thesis studies the Growth Curve model in multivariate statistics which is a model that is not widely used. One difference compared with the linear model is that the Maximum Likelihood Estimators are more complicated. That makes it more difficult to use and to interpret which may be a reason for its not so widespread use. From this perspective this thesis will compare the traditional mean estimator for the Growth Curve model with the unweighted mean estimator. The unweighted mean estimator is simpler than the regular MLE. It will be proven that the unweighted estimator is in fact the MLE under certain conditions and examples when this occurs will be discussed. In a more general setting this thesis will present conditions when the un-weighted estimator has a smaller covariance matrix than the MLEs and also present confidence intervals and hypothesis testing based on these inequalities.
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The Effect of STEM and non-STEM Education on Student Mathematics Ability in Third GradeHyacinth, Elke 01 January 2019 (has links)
Although early mathematics instruction is predictive of future mathematics achievement, the effects of STEM-based mathematics instruction on mathematics gains in elementary school have been largely unexplored. The purpose of this quantitative study was to determine whether mathematics scores from third grade student state-mandated standardized mathematics test differ between students who were enrolled in STEM schools and students who were enrolled in non-STEM schools in the largest school district located in a Southwestern state in the United States. Polya's problem-solving heuristics formed the theoretical framework because of their relevance to concepts on the third grade mathematics test. Two research questions focused on intraindividual changes and interindividual changes over time in standardized mathematics test scores of third grade students who were enrolled in 18 STEM and 18 non-STEM schools. Analyses included growth curve modeling and a one-way random effect ANOVA to determine individual growth trajectories of mathematics test scores from individual schools over time from 2012 through 2017. The results indicated that there were no intraindividual differences in growth over time within schools, and there were interindividual changes in growth over time between schools, but the changes could not be explained by the independent variables, STEM and non-STEM schools. Findings were not consistent with the literature, which indicated early STEM-based mathematics instruction is more beneficial than traditional instruction. This study offers implications for positive social change by demonstrating equivalent results of STEM to non-STEM instruction, which may encourage more hands-on, inquiry-based learning for all children.
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Associations longitudinales entre le soutien maternel à l’autonomie et la performance en mathématiques chez les enfants au primaire : analyses par courbes de croissanceCimon-Paquet, Catherine 08 1900 (has links)
Un nombre grandissant d’études suggère que le soutien maternel à l’autonomie pourrait favoriser une meilleure performance scolaire chez les enfants. Or, peu d’études longitudinales ont examiné l’apport du soutien à l’autonomie précoce dans la prédiction des trajectoires développementales du rendement en mathématiques durant les premières années d’école, bien que l’évolution des habiletés en mathématiques au cours du primaire soit bien documentée. De plus, l’interaction entre le soutien maternel à l’autonomie et les capacités cognitives de base de l’enfant n’a jamais été examinée dans la prédiction de trajectoires de rendement scolaire, bien que de telles interactions soient attendues théoriquement. La présente étude avait pour objectif d’examiner l’interaction entre le soutien maternel à l’autonomie et les capacités cognitives de l’enfant, mesurés durant la petite enfance, dans la prédiction des trajectoires de rendement en mathématiques de la première année à la troisième année du primaire. L’échantillon était constitué de 113 dyades mère-enfant. Le soutien maternel à l’autonomie a été mesuré par observation d’interactions mère-enfant, tandis que les capacités cognitives de base et le rendement en mathématiques de l’enfant ont été mesurés à l’aide d’outils standardisés. Les résultats suggèrent que le soutien maternel à l’autonomie précoce est associé à la performance en mathématiques au cours du primaire, mais que cette relation se présente différemment selon les capacités cognitives de base de l’enfant. Cette étude suggère que le soutien maternel à l’autonomie durant les premières années de vie de l’enfant pourrait potentiellement favoriser le développement de compétences en mathématiques à long terme. / Increasing evidence suggests that maternal autonomy support fosters academic achievement in children. However, despite evidence that mathematical achievement evolves markedly during elementary school years, no study has examined early autonomy support in relation to mathematical achievement trajectories. Moreover, few studies have considered the role of child general cognitive abilities in these associations. With a sample of 113 mother–child dyads, the current study investigated whether patterns of growth in mathematical achievement during the first three years of elementary school were predicted by the interaction between maternal autonomy support and child general cognitive abilities, both assessed in infancy. Maternal autonomy support was assessed based on videotaped mother–child interactions, whereas child general cognitive abilities and mathematical achievement were assessed using standardised tests. Results suggest that early maternal autonomy support predicts later mathematical development in children, although this relation unfolds differently based on children’s baseline cognitive abilities. These findings suggest that maternal autonomy support in the first years of life may confer long-lasting benefits for children’s acquisition of mathematical knowledge.
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