17 results on '"Cargnelutti Filho, Alberto"'
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2. Number of trials to estimate the condition number in rye traits.
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Márcio Neu, Ismael Mario, Cargnelutti Filho, Alberto, Lixinski Silveira, Daniela, Vieira Pezzini, Rafael, and Tolfo Bandeira, Cirineu
- Abstract
Multicollinearity must be diagnosed in multivariate analyses. Among the indicators, the condition number can be used to quantify the degree of multicollinearity. Hence, this study sought to determine the number of measurements (trials) necessary to estimate the number of condition in linear correlation matrices between rye traits. Five uniformity trials were carried out with 'BRS Progresso' rye, and eight morphological traits and eight productive traits were evaluated, forming two groups. In each group of traits, six cases (combinations of traits) were planned and the multicollinearity diagnosis was performed. Repeatability analyses were performed using the following methods: analysis of variance, principal component analysis, and structural analysis, and the number of measurements (trials) was determined for different levels of precision. A higher condition number of repeatability coefficients was obtained by the principal component methods (based on correlation and variance and covariance matrices) and structural analysis based on the variance and covariance matrix. A greater number of measurements (trials) is necessary to estimate the number of conditions in productive traits compared to morphological ones. One trial is enough to efficiently estimate the condition number with a minimum accuracy of 80% in morphological and productive traits of rye, whereas at least three trials are required for 95% accuracy. [ABSTRACT FROM AUTHOR]
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- 2023
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- View/download PDF
3. Plot size and number of repetitions in forage wheat.
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Bubans, Valéria E., Cargnelutti Filho, Alberto, Neu, Ismael M. M., Silveira, Daniela L., Somavilla, Felipe M., and Osmari, Bruno F.
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AGRICULTURE ,FIELD research ,BLOCK designs ,CULTIVARS ,GROUND cover plants ,WHEAT ,EXPERIMENTAL design ,COVER crops - Abstract
Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2023
- Full Text
- View/download PDF
4. Sample size for evaluating the height and diameter of seedlings pecan
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Cargnelutti Filho,Alberto, Poletto,Tales, Muniz,Marlove Fátima Brião, Baggiotto,Carine, Poletto,Igor, and Fronza,Diniz
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planejamento experimental ,sampling ,Carya illinoinensis ,amostragem ,experimental planning - Abstract
O objetivo deste trabalho foi determinar o tamanho de amostra (número de plantas) necessário para a estimação da média de altura de planta, do diâmetro do coleto e da relação altura de planta/diâmetro do coleto de mudas de nogueira-pecã (Carya illinoinensis) e verificar a variabilidade do tamanho de amostra entre tratamentos de superação de dormência de sementes. Foram avaliados 12 tratamentos de superação de dormência de sementes e, aos 98 dias após a semeadura, foram mensurados os caracteres altura de planta (H) e diâmetro do coleto (D), e calculada a relação altura de planta/diâmetro do coleto (HD). Foram calculadas medidas de tendência central e de variabilidade, verificadas a normalidade e a homogeneidade de variâncias e calculado o tamanho de amostra. O tamanho de amostra para avaliar H, D e HD de mudas de nogueira-pecã é dependente do tratamento para superação de dormência de sementes. Sessenta e três plantas são suficientes para a estimação da média de H, do D e da HD de mudas de nogueira-pecã, para erro de estimação de 10% da média estimada, com grau de confiança de 95% The aim of this research was to determine the sample size (number of plants) necessary to estimate the average plant height, collar diameter and relation plant height/collar diameter of seedlings pecan (Carya illinoinensis) and to verify the variability of the sample size among treatments of overcoming seed dormancy. It was evaluated 12 treatments of overcoming seed dormancy and at 98 days after sowing it was measured the plant height (H) and collar diameter (D) and calculated the relation plant height/collar diameter (HD). Measures of central tendency and variability were calculated, the normality and homogeneity of variances were verified and sample size was calculated. The sample size to evaluate H, D e HD is dependent on treatments of overcoming seed dormancy. Sixty-three plants enough to predict the average of H, D and HD seedlings pecan, with an estimation error equal to 10% of estimated average, with a degree confidence of 95%
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- 2014
5. Dimensionamento amostral para avaliação de altura e diâmetro de mudas de Cabralea canjerana
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Cargnelutti Filho, Alberto, Araujo, Maristela Machado, Gasparin, Ezequiel, and Avila, Angela Luciana de
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planejamento experimental ,experimental precision ,sampling ,Canjerana ,precisão experimental ,amostragem ,experimental planning - Abstract
Em viveiros florestais, é importante determinar o número de plantas a serem avaliadas para que as inferências sobre crescimento das mudas sejam confiáveis. O objetivo deste trabalho foi estimar o tamanho de amostra (número de plantas) necessário para avaliar a altura de planta, o diâmetro do coleto e a relação altura de planta/diâmetro do coleto de mudas de canjerana (Cabralea canjerana (Vell.) Mart.) e verificar a variabilidade do tamanho de amostra entre tubetes, substratos e idades de avaliação. Foi conduzido um experimento, em viveiro, no qual foram avaliados nove tratamentos, formados pela combinação de três tamanhos de tubetes (100, 180 e 280cm³) e três tipos de substratos (100% de turfa, 80% de turfa + 20% de casca de arroz carbonizada e 60% de turfa + 40% de casca de arroz carbonizada), no delineamento experimental em blocos ao acaso, com quatro repetições. Em dez idades de avaliação, foram mensurados os caracteres altura de planta e diâmetro do coleto, e calculada a relação altura de planta/diâmetro do coleto, em dez plantas, tomadas aleatoriamente, na área central de cada unidade experimental. Foram realizadas análises de variância, testes de comparação de médias, verificação de normalidade e calculado o tamanho de amostra. O tamanho de amostra para avaliar a altura de planta, o diâmetro do coleto e a relação altura de planta/diâmetro do coleto de mudas de canjerana é dependente da idade de avaliação. Para os tubetes, substratos e idades de avaliação estudados, 18 plantas por unidade experimental (bandeja) são suficientes para a estimação da média desses caracteres, para um erro de estimação igual a 10% da média estimada, com grau de confiança de 95%. In nurseries, it is important to determine the number of plants to be evaluated so that inferences about seedling growth are reliable. The aim of this research was to estimate the sample size (number of plants) necessary to evaluate plant height, collar diameter and relation plant height/collar diameter of canjerana seedlings (Cabralea canjerana (Vell.) Mart.) and to verify its variability among tubes, substrates and ages evaluation. An experiment was conducted in the nursery, in which nine treatments, organized in randomizes blocks design with four replication, were formed by the combination of three sizes of tubes (100, 180 and 280cm³) and three substrates (100% peat, 80% peat + 20% rice hulls and 60% peat + 40% rice hulls). It was evaluated the following characters, in ten ages: plant height, collar diameter and relation plant height/collar diameter, in ten plants sampled at random in each experimental unit. Analyses of variance, means comparison tests and verification of normality were carried and the sample size was calculated. The sample size to evaluate the plant height, collar diameter and relation plant height/collar diameter of canjerana seedlings is dependent on age evaluation. For the tubes, substrates and ages evaluation studied, 18 plants per experimental unit (pot) are enough to predict the these characters average, with an estimation error equal to 10% of estimated average, with a degree confidence of 95%.
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- 2012
6. Tamanho de amostra para a estimação da média de caracteres de pêssego na colheita e após o armazenamento refrigerado
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Toebe, Marcos, Both, Vanderlei, Brackmann, Auri, Cargnelutti Filho, Alberto, and Thewes, Fabio Rodrigo
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Prunus persica ,planejamento experimental ,sample dimensioning ,dimensionamento de amostra ,experimental planning - Abstract
O objetivo deste trabalho foi determinar o tamanho de amostra necessário para avaliar caracteres de frutos de pêssego na colheita e após o armazenamento refrigerado. Foram colhidos frutos de um pomar comercial. No laboratório, separaram-se, aleatoriamente, duas amostras de 120 frutos de pêssego, sendo uma amostra avaliada na colheita e a outra armazenada a -0,5°C por 30 dias, mais cinco dias a 20°C. Foram mensurados 11 caracteres em cada fruto na colheita e 12 caracteres após o armazenamento refrigerado, sendo calculadas medidas de tendência central e de dispersão e verificada a normalidade. Posteriormente, compararam-se as médias e verificou-se a homogeneidade de variâncias dos caracteres avaliados na colheita e após o armazenamento refrigerado. A seguir, foi determinado o tamanho de amostra para cada caractere. São necessários 169 frutos para estimar a firmeza de polpa, 34 frutos para estimar a massa, a acidez e o ratio, 11 frutos para avaliar a suculência e seis frutos para estimar os demais caracteres na colheita e após o armazenamento refrigerado, com erro de estimação de 5% da média. The aim of this research was to determine the sample size needed to evaluate peach fruit characters at harvest and after cold storage. Fruits were collected from a commercial orchard. In the laboratory, split randomly, two samples of 120 fruits each, one sample assessed at harvest and one stored at -0.5°C for 30 days, and then for five additional days at 20°C. Eleven characters were measured on each fruit at harvest and twelve after cold storage, being the central tendency measures and dispersion calculated and normality checked. After, it was compared the average and the homogeneity of variance at harvest and after cold storage and calculated the sample size for each character. In peach, 169 fruits are needed to estimate the pulp firmness, 34 fruits to estimate the weight, acidity and ratio, 11 fruits to assess fruit juiciness and six fruits to estimate the others characters at harvest and after cold storage, with an estimation error of 5% on average.
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- 2012
7. Tamanho de amostra para estimação do coeficiente de correlação de Pearson entre caracteres de Crambe abyssinica
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Cargnelutti Filho, Alberto, Lopes, Sidinei José, Toebe, Marcos, Silveira, Tatiani Reis da, and Schwantes, Ismael Albino
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Planejamento experimental ,Crambe ,Experimental planning ,Experimental precision ,Precisão experimental - Abstract
É importante dimensionar adequadamente o tamanho de amostra, para estimação, com confiabilidade aceitável, do coeficiente de correlação linear de Pearson entre pares de caracteres. O objetivo deste experimento foi determinar o tamanho de amostra (número de plantas) para estimação do coeficiente de correlação linear de Pearson, entre 21 caracteres de crambe (Crambe abyssinica Hochst). Um experimento em campo foi conduzido no ano de 2008. Na colheita foram selecionadas, aleatoriamente, 75 plantas, nas quais foram mensurados 21 caracteres. Foram calculadas medidas de tendência central, de variabilidade, de assimetria e de curtose, verificada a normalidade e investigada a linearidade entre os caracteres. Foi calculado o tamanho de amostra, para estimação do coeficiente de correlação de Pearson, para as amplitudes do intervalo de confiança de 95%, iguais a: 0,15; 0,20; 0,25; 0,30; 0,35 e 0,40, para cada um dos 210 pares de caracteres. Para os 210 pares de caracteres de crambe estudados, o tamanho de amostra, para estimação do coeficiente de correlação linear de Pearson, para a amplitude do intervalo de confiança de 95% igual a 0,15, oscilou entre 8 e 665 plantas. It is important to dimension correctly the sample size, to estimate the Pearson correlation coefficient among pairs of characters, with acceptable reliability. The aim of this research was to determine the sample size (number of plants) to estimate the Pearson correlation coefficient among 21 characters of crambe (Crambe abyssinica Hochst). An experiment was conducted in the year 2008. At harvest, 75 plants were selected randomly and measured 21 characters. The measures of central tendency, variability, skewness and kurtosis, were done. Normality was verified and investigated the linearity among the characters. The sample size to estimate the Pearson correlation coefficient was calculated, for the amplitude of the confidence interval of 95%, equal to: 0.15; 0.20; 0.25; 0.30; 0.35 and 0.40, for each of 210 pairs of characters. For the 210 characters pairs of crambe, the sample size to estimate the Pearson correlation coefficient, to the amplitude of the confidence interval of 95% equal to 0.15, ranged from 8 to 665 plants.
- Published
- 2011
8. Medidas do grau de precisão experimental em ensaios de competição de cultivares de milho
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Cargnelutti Filho, Alberto and Storck, Lindolfo
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planejamento experimental ,controle de qualidade ,produtividade de grãos ,grain yield ,quality control ,Zea mays ,experimental planning - Abstract
O objetivo deste trabalho foi avaliar a adequação de algumas estatísticas como medidas do grau de precisão experimental, e as relações entre elas. Foram usados os dados de produtividade de grãos de 101 ensaios de competição de cultivares de milho (Zea mays L.), realizados no Estado do Rio Grande do Sul, nos anos agrícolas 2002/2003, 2003/2004 e 2004/2005. Foi estudada a relação entre 12 estatísticas, estimadas para cada ensaio, e as análises de correlação de trilha e de agrupamento foram realizadas com base nessas estatísticas. Os limites de classe estabelecidos, a partir das estatísticas acurácia seletiva, herdabilidade, coeficiente de determinação e valor do teste F para cultivar, mostraram-se adequados para estimar o grau de precisão experimental de ensaios de competição de cultivares de milho. Por essas estatísticas, 89% dos ensaios de competição de cultivares de milho apresentaram precisão alta ou muito alta e 5% dos ensaios poderiam ser escartados em razão da insuficiência na precisão experimental. As estatísticas acurácia seletiva, herdabilidade, coeficiente de determinação e valor do teste F para cultivar têm relação direta entre si e são mais adequadas do que o coeficiente de variação e a diferença mínima significativa pelo teste de Tukey, em percentagem da média, para avaliação da precisão experimental em ensaios de competição de cultivares de milho. The objective of this work was to evaluate the appropriateness of some statistics as experimental precision measures and the relationships among them. Grain yield data from 101 cultivar competition trials of corn (Zea mays L.), which were carried out in the Rio Grande do Sul state, Brazil, in the agricultural years 2002/2003, 2003/2004 and 2004/2005, were used. Relationship among 12 statistics, estimated from each trial, was studied and correlation, path and cluster analysis were calculated based on these statistics. Class limits established by the statistics selective accuracy, heritability, coefficient of determination and F test value for cultivar were adequate to estimate the degree of experimental precision in corn yield trials. According to these statistics, 89% of the experiments showed a high or very high degree of precision and 5% of experiments could be discarded due to insufficient experimental precision. The statistics selective accuracy, heritability, coefficient of determination and F test value for cultivar show a direct relationship among them and are more adequate than the coefficient of variation and the significant minimum difference among cultivars by Tukey's test, expressed in percentage of the mean, to evaluate the experimental precision of corn yield trials.
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- 2009
9. Tamanho de amostra de caracteres de genótipos de soja
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Cargnelutti Filho, Alberto, Evangelista, Dilson Henrique Ramos, Gonçalves, Elaine Cristine Piffer, and Storck, Lindolfo
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planejamento experimental ,experimental precision ,Glycine max L ,sampling ,precisão experimental ,amostragem ,experimental planning - Abstract
O objetivo deste trabalho foi estimar o tamanho de amostra necessária para avaliar caracteres de genótipos de soja (Glycine max L.) e verificar a variabilidade do tamanho de amostra entre genótipos e entre experimentos. Para tanto, 28 genótipos de soja foram avaliados em cinco experimentos conduzidos em Jaboticabal, Estado de São Paulo (latitude 21°15'22"S, longitude 48°18'18" W e 595m de altitude), nos anos agrícolas de 2002 a 2005. Foi utilizado o delineamento de blocos ao acaso, com três repetições, e foram avaliados os caracteres altura de planta na maturação e de inserção de primeira vagem, número de nós por planta, de ramos por planta e de vagens por planta em seis plantas amostradas aleatoriamente na parcela. Há variabilidade da estimativa do tamanho de amostra entre genótipos quanto ao número de nós por planta e entre experimentos quanto à altura de planta na maturação, ao número de nós por planta, de ramos por planta e de vagens por planta. Para melhorar a precisão da avaliação de caracteres em plantas de soja, deve-se usar maior número de repetições e, pelo menos, 12 plantas por unidade experimental. The aim of this research was to determine the sample size of characters in different soybeans (Glycine max L.) genotypes and to verify its variability among genotypes and experiments. Twenty-eight soybeans genotypes were evaluated in five experiments conducted in Jaboticabal, São Paulo State, Brazil (latitude 21°15'22"S, longitude 48°18'18" W, altitude 595m), in agricultural years from 2002 to 2005. Randomized blocks design with three repetitions was installed to evaluate the following characters: plant height at maturity, height of first pod insertion, number of nodes per plant, number of branches per plant and number of pods per plant, in six plants sampled at random in each plot. It was found variability in the sample size among genotypes in relation to the number of nodes per plant. When the five experiments were compared, results also show variability of the sample size in relation to plant height at maturity, number of nodes per plant, number of branches per plant and number of pods per plant. To improve the experimental precision in the evaluation of characters in soybeans plants it is recommended to increase the number of repetitions and use, at least, twelve plants per plot.
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- 2009
10. Sample size for estimating average trunk diameter and plant height in eucalyptus hybrids.
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Cargnelutti Filho, Alberto, Beltrame, Rafael, Bisognin, Dilson Antônio, Lazarotto, Marília, Haselein, Clovis Roberto, Gatto, Darci Alberto, and dos Santos, Gleison Augusto
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EUCALYPTUS , *SAMPLE size (Statistics) , *TREE trunks , *ANALYSIS of variance , *TREES - Abstract
In eucalyptus crops, it is important to determine the number of plants that need to be evaluated for a reliable inference of growth. The aim of this study was to determine the sample size needed to estimate average trunk diameter at breast height and plant height of inter-specific eucalyptus hybrids. In 6,694 plants of twelve inter-specific hybrids it was evaluated trunk diameter at breast height at three (DBH3) and seven years (DBH7) and tree height at seven years (H7) of age. The statistics: minimum, maximum, mean, variance, standard deviation, standard error, and coefficient of variation were calculated. The hypothesis of variance homogeneity was tested. The sample size was determined by re sampling with replacement of 10,000 re samples. There was an increase in the sample size from DBH3 to H7 and DBH7. A sample size of 16, 59 and 31 plants is adequate to estimate DBH3, DBH7 and H7 means, respectively, of inter-specific hybrids of eucalyptus, with amplitude of confidence interval of 95% equal to 20% of the estimated mean. [ABSTRACT FROM AUTHOR]
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- 2016
- Full Text
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11. Tamanho de parcela e número de repetições em feijão guandu.
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Oliveira dos Santos, Gustavo, Cargnelutti Filho, Alberto, Mendonça Alves, Bruna, Burin, Cláudia, Facco, Giovani, Toebe, Marcos, Kleinpaul, Jéssica Andiara, Márcio Neu, Ismael Mario, and Bellé Stefanello, Réges
- Abstract
The objectives of this research were to determine the optimum plot size and number of repetitions, to evaluate the fresh weight of pigeonpea (Cajanus cajan (L.) Millsp.), in times and years. Eighty uniformity trials of 6m×6m (36m2) were conducted. Each trial was divided in 36 basic experimental units (BEU) of 1m×1m, totaling 2,880BEU. The fresh weight of plants, in each BEU was weighed. The agricultural year 2011/2012, were evaluated 16 trials at 127 days after sowing (DAS) and 24 to 139DAS. In 2012/2013, four trials at each of times (163, 167, 170, 174, 177, 181, 184, 188, 191 and 195DAS) were evaluated. The optimum plot size was determined by the method of maximum curvature of the coefficient of variation model and the means compared, among evaluation times and years, by Scott-Knott test. The number of repetitions, in scenarios of combinations of i treatments (i=3, 4, ..., 50) and d minimal differences between treatments means, to be detected as significant, 5% probability by Tukey's test, expressed in percentage of experiment avarage (d=10%, 15%, ..., 50%), was determined by iterative process until convergence. The optimum plot size to evaluate the fresh weight of pigeonpea is was 8.39m2. Four replications, to evaluate up to 50 treatments, are sufficient to identify, as significant at 5% probability by Tukey's test, differences between treatment means of 54.1% of the average experiment. [ABSTRACT FROM AUTHOR]
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- 2016
- Full Text
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12. Tamanho de amostra para a estimação da média de caracteres morfológicos e produtivos de nabo forrageiro.
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Cargnelutti Filho, Alberto, Facco, Giovani, Dal'Col Lúcio, Alessandro, Toebe, Marcos, Burin, Cláudia, Fick, André Luis, and Márcio Neu, Ismael Mario
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TURNIPS , *SOWING , *PLANT morphology , *SAMPLING errors , *SAMPLING (Process) - Abstract
The aim of this research was to determine the sample size to estimate the average of morphological and productive traits of turnip (Raphanus sativus L.). In a experiment, 300 plants were randomly selected and measured for morphological traits (plant height and number of leaf at 21, 35, 48, 55, 62, 70, 77 and 91 days after sowing) and productive (fresh and dry matter of roots, stem, leaf and total of 91 days after sowing). Measures of central tendency and variability were calculated, normality was checked and the sample size was calculated. The sample size of productive traits is greater than morphological to estimate average and it has the same precision. For the morphological and productive traits studied 231 plants are enough to predict the average, with an estimation error maximum of 10% of estimated average, with a degree confidence of 95%. [ABSTRACT FROM AUTHOR]
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- 2014
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13. Sample size for estimation of the plastochron in pigeonpea
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Cargnelutti Filho, Alberto, Toebe, Marcos, Facco, Giovani, Santos, Gustavo Oliveira dos, Alves, Bruna Mendonça, and Bolzan, Anderson
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PIGEON pea , *FLOWERING of plants , *ESTIMATION theory , *ATMOSPHERIC temperature , *LEAF area index , *REGRESSION analysis , *THERMAL analysis - Abstract
Abstract: The objectives of this study were to estimate the plastochron in pigeonpea (Cajanus cajan (L.) Millsp.) during the period between emergence and flowering using three methods of calculating the average daily air temperature and to determine the sample size (number of plants) needed to estimate the plastochron. A uniformity test (blank experiment) was conducted in an area of 1440m2 containing a pigeonpea crop. The area was divided into 360 plots of 2m×2m, and 1 plant per plot was marked at random. In each of these 360 plants, the number of nodes on the main stem was counted at 37, 43, 50, 57, 64, 71, 78, 85, 93, 99, 106, 114 and 120 days after emergence (DAE). The average daily air temperature (T average) was calculated using three methods: method 1: T average =(T minimum + T maximum)/2; method 2: T average =(T 0h + T 1h + T 2h +⋯+T23h)/24; and method 3: T average =(T minimum + T maximum + T 9h +2T 21h)/5. For the three methods, the daily and cumulative thermal times were calculated from the date of emergence to early flowering and fitted to a linear regression of the average number of nodes on the main stem as a function of the accumulated thermal time. The plastochron was then calculated under each method as the inverse of the slope of the linear regression, and the required sample size (number of plants) to estimate the plastochron was determined by resampling with replacement. Plastochron values determined from the average daily air temperature calculated based on the three methods are different, and the use of the arithmetic mean of the hourly temperatures (method 2) should be favoured. Under method 2, the plastochron for pigeonpea was determined to be 21.34°Cdaynode−1. To estimate the plastochron with 95% confidence interval amplitudes equal to 1, 2 and 3°Cdaynode−1, it was necessary to count the number of nodes in 194, 50 and 24 pigeonpea plants, respectively. [Copyright &y& Elsevier]
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- 2013
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14. How many cauliflower seedlings are necessary to estimate experimental precision statistics reliably?
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Bittencourt, Karina Chertok, Souza, Rafael Rodrigues de, Pazetto, Stella Bonorino, Toebe, Marcos, Toebe, Iris Cristina Datsch, and Cargnelutti Filho, Alberto
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STATISTICAL accuracy , *SAMPLE size (Statistics) , *CAULIFLOWER , *AGRICULTURAL forecasts , *PRINCIPAL components analysis , *CONFIDENCE intervals , *SEEDLINGS - Abstract
The aims of this study were to determine the adequate sample size of cauliflower seedlings per experimental unit to estimate experimental precision statistics, and to forecast experimental precision statistics. From a reference experiment in which 20 seedlings per experimental unit were sampled and the number of leaves, shoot length, root length, and total length were measured, a bootstrapping procedure was applied with replacement, recreating experiments with sample sizes ranging from 1 to 100 seedlings per experimental unit, obtaining 10,000 resamples for each size. For each resample, 13 precision statistics were estimated, for which the 95% confidence interval widths were calculated, fitting these values to the sampling scenarios through traditional power models. The sample size was then determined through the maximum curvature point through the perpendicular distances' method for each precision statistic and trait, for which a modified power model was used for forecasting. Also the contribution of the precision statistics to sample size definition was verified via principal component analysis. The reference experiment showed high experimental precision, which varied according to the trait and precision statistic considered. An exponential decrease in the confidence interval width was observed as the sample number was increased, and the optimal sample size varied slightly among statistics and traits, where the maximum value found was 20 seedlings per experimental unit, however, considering the statistics that contributed the most to the total variation, 16 seedlings per experimental unit represent the sufficient sample size for estimating experimental precision statistics in experiments with cauliflower seedlings. Also, the forecasting models showed excellent fitting quality and can be used and adapted by researchers performing experiments on seedling production of cauliflower or other horticultural crops. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2023
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15. Sample size and modeling of plant variability using precision statistics in soybean counting traits.
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Souza, Rafael Rodrigues de, Toebe, Marcos, Marchioro, Volmir Sergio, Cargnelutti Filho, Alberto, Bittencourt, Karina Chertok, Mello, Anderson Chuquel, and Paraginski, João Antônio
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STATISTICAL accuracy , *PLANT size , *SAMPLE size (Statistics) , *PILOT plants , *CONFIDENCE intervals - Abstract
Counting traits are commonly measured in soybean research, however, the number of plants to be sampled per experimental unit needs to be standardized for estimating precision statistics from these traits, considering experimental designs; The current study evaluated the impact of plant variability for selected soybean agronomic traits; established the ideal sample size to estimate experimental precision statistics; and modeled the response of plant variability per experimental unit to forecast experimental precision statistics; Trials were conducted with 30 genotypes in highlands and 20 in lowland areas of Brazil. A complete randomized block design with three repetitions was used, measuring four counting traits in 20 plants per experimental unit, which represents a total of 9000 plants. From these experiments, trials with sampling scenarios from 1 to 100 plants per experimental unit were simulated; Results showed an exponential decreasing response of the 95% confidence intervals as a function of the increase in sample size per experimental unit for all precision statistics, stabilizing when ≥ 21 plants per experimental unit were sampled. Twenty-one plants per experimental unit were considered representative for the soybean traits here studied. The response of the 95% confidence interval width to sample size enabled the creation of good-quality forecasting formulas and equations to predict experimental precision in experiments with soybean that evaluate these traits; The sample size recommendations made in this work can be applied in similar experimentations. [Display omitted] • Twenty-one plants per experimental unit were enough for soybean counting traits. • Precision statistics were predicted from subtropical-climate soybean counting traits. • Forecasting precision improved after reaching 21 plants per experimental unit. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
16. Soybean yield variability per plant in subtropical climate: sample size definition and prediction models for precision statistics.
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Souza, Rafael Rodrigues de, Toebe, Marcos, Marchioro, Volmir Sergio, Cargnelutti Filho, Alberto, Lúcio, Alessandro Dal'Col, Benin, Giovani, Mello, Anderson Chuquel, Tartaglia, Francieli de Lima, and Manfio, Guilherme Liberalesso
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STATISTICAL accuracy , *TROPICAL plants , *SAMPLE size (Statistics) , *MOUNTAIN climate , *PREDICTION models , *SOYBEAN - Abstract
Empirical decision-making on the number of plants to be sampled per experimental unit when assessing soybean grain yield is a commonly observed situation. The cause for this is unknowing how that decision affects experimental precision statistics, which has not yet been reported. Therefore, the aims of this study were: to analyze the response of experimental precision statistics as a function of the variations in the number of plants collected per experimental unit in highland and lowland systems; to define the optimal sample size per experimental unit for each precision statistic; and, to propose predictive models for estimating the precision of experiments with soybean. Field experiments were carried out in two locations of Rio Grande do Sul, Brazil, using 30 cultivars in the highland trials and 20 cultivars in the lowland trials. A validation trial was also performed using 8 cultivars. A randomized block design with three repetitions was used for all trials. The grain yield of 20 plants per experimental unit was assessed, thus totaling 9000 plants. In the validation experiment, grain yield was measured in 100 plants per experimental unit, totaling 2400 plants more. From these experiments, trials with sample scenarios of 1, 2, ..., 1000 plants per experimental unit were simulated with replacement. The confidence interval width of the precision statistics reduced as the number of plants measured per experimental unit increased, allowing a higher precision of its estimates. In general, up from values of ≥ 70%, precision gain, in the estimates of experimental precision statistic determined in soybean highland and lowland systems, tends to stabilize. The optimal sample number per experimental unit varied between systems and experimental precision statistics. The sampling of 18 plants per experimental unit is sufficient to estimate most precision indicators reliably. Interestingly, the mechanistic response of the confidence interval width is easily modeled and can be used for predicting experimental precision in highland and lowland cropping systems. From this analysis, a methodology for predicting experimental precision was outlined based on sample size per experimental unit, thus bringing new insight into future experimental planning for soybean experiments in highland and lowland systems in subtropical climate. [Display omitted] • The accuracy of the precision statistics was improved in greater sampling scenarios. • Eighteen plants per experimental unit were sufficient in highlands and lowlands. • The proposed methodology is adequate for subtropical climate highlands and lowlands. • Precision predictability is improved in samplings ≥ 18 plants per experimental unit. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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17. Plot size and number of repetitions to evaluate the green mass of aerial part in pigeonpea
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Santos, Gustavo Oliveira dos, Cargnelutti Filho, Alberto, Lopes, Sidinei José, and Lorentz, Leandro Homrich
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Planejamento experimental ,Experimental planning ,Experimental precision ,CIENCIAS AGRARIAS::AGRONOMIA [CNPQ] ,Precisão experimental ,Cajanus cajan - Abstract
A good planning of experiment should be related to the optimization of the size of the plots and the number of repetitions. Thus, the objectives of this study were: determine the portion size and the number of repetitions to evaluate the green mass of pigeonpea shoots and compare estimates of the size of portion between times of assessment in the same year and between years. Two tests were conducted of uniformity with pigeonpea (Cajanus cajan (L.) Millsp.) cultivar BRS Mandarin in two years 2011/2012 and agricultural 2012/2013. In the year 2011/2012, agricultural to 127 days after sowing (DAS), the evaluation was conducted of the first season, where they were evaluated 16 tests with 36 basic experimental units (UEB) of 1 m² were weighed in grams, plants were cut along the surface of the ground to evaluate the aboveground green mass in grams m-² in digital electronic personal scale. This methodology was used in all evaluations. The second time was evaluated to 139 of, with 24 essays composed 36 UEB of 1 m². In the year 2012/2013 agricultural assessments were conducted in 10 seasons to163, 167, 170, 174, 177, 181, 184, 188, 191 and 195 of, each season was rated 4 trials with 36 UEB of 1 m². For each test, were determined the spatial autocorrelation coefficient of first order (ρ), variance (s²), medium (m), the coefficient of variation (CV) assay, the great size of plot (Xo) and the coefficient of variation in size of parcel (CVXo) as Paranaíba; Ferreira; Morais (2009a). The comparison of the averages statistics ρ, s², m, CV, Xo and CVXo, between the times of assessment in each year between agricultural and agricultural, regardless of time, was accomplished using student's t test for independent samples, the 5% probability of error using bootstrap with 10000 simulations. The number of repetitions was determined by iterative process for experiments in completely randomized design (DIC) and random blocks design (DBA). The great size of plot to evaluate the green mass of aerial part of pigeonpea differs between seasons in the same year assessment and does not differ between the years, regardless of the time of evaluation. Because there are significant differences between the eras of evaluation within each year, the great size of plot to evaluate the green mass of aerial part of pigeonpea was estimated at 8.39 m ², contemplating this way, every season for the evaluation of two years. To evaluate the green mass of aerial part of pigeonpea with CVXo = 18.76% and Xo = 8.39 m², seven repetitions are enough in experiments in DIC and DBA with up to 50 treatments to identify the 5% probability, by Tukey test, significant differences between averages of treatments of 40% of the average of the experiment. Um bom planejamento de experimento deve estar relacionado com a otimização do tamanho das parcelas e do número de repetições. Assim, os objetivos deste trabalho foram: determinar o tamanho de parcela e o número de repetições para avaliar a massa verde da parte aérea do feijão guandu e, comparar as estimativas do tamanho ótimo de parcela entre épocas de avaliação no mesmo ano e entre anos. Foram realizados dois ensaios de uniformidade com feijão guandu (Cajanus cajan (L.) Millsp.) cultivar BRS Mandarim em dois anos agrícolas 2011/2012 e 2012/2013. No ano agrícola 2011/2012, aos 127 dias após a semeadura (DAS), foi realizada a avaliação da primeira época, onde foram avaliados 16 ensaios com 36 unidades experimentais básicas (UEB) de 1m² que foram pesadas em gramas, as plantas foram cortadas junto à superfície do solo para avaliar a massa verde da parte aérea, em gramas m-², em balança eletrônica digital. Esta metodologia foi utilizada em todas as avaliações. A segunda época foi avaliada aos 139 DAS, com 24 ensaios compostos por 36 UEB de 1m². No ano agrícola 2012/2013 as avaliações foram realizadas em dez épocas, ou seja, aos 163, 167, 170, 174, 177, 181, 184, 188, 191 e 195 DAS, sendo que em cada época foram avaliados 4 ensaios com 36 UEB de 1m². Para cada ensaio, foram determinados o coeficiente de autocorrelação espacial de primeira ordem (ρ), a variância (s2), a média (m), o coeficiente de variação do ensaio (CV), o tamanho ótimo de parcela (Xo) e o coeficiente de variação no tamanho ótimo de parcela (CVXo), conforme Paranaíba; Ferreira; Morais (2009a). A comparação das médias das estatísticas ρ, s2, m, CV, Xo e CVXo, entre as épocas de avaliação em cada ano agrícola e entre os anos agrícolas, independentemente de época, foi realizada por meio do teste t de Student para amostras independentes, a 5% de probabilidade de erro utilizando bootstrap com 10.000 simulações. O número de repetições foi determinado por processo iterativo para experimentos no delineamento inteiramente casualizado (DIC) e delineamento blocos ao acaso (DBA). O tamanho ótimo de parcela para avaliar a massa verde da parte aérea de feijão guandu difere entre as épocas de avaliação no mesmo ano e não difere entre os anos, independentemente da época de avaliação. Por haver diferenças significativas entre as épocas de avaliação dentro de cada ano, o tamanho ótimo de parcela para avaliar a massa verde da parte aérea de feijão guandu foi estimado em 8,39m², contemplando dessa forma, todas as épocas de avaliação dos dois anos agrícolas. Para avaliar a massa verde da parte aérea do feijão guandu com CVXo=18,76% e Xo=8,39m2, sete repetições são suficientes em experimentos no DIC e no DBA com até 50 tratamentos para identificar em 5% de probabilidade, pelo teste de Tukey, diferenças significativas entre médias de tratamentos de 40% da média do experimento.
- Published
- 2014
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