TY - JOUR
T1 - Enfoque estadístico para evaluar la heterogeneidad de paltas Hass, sometidas a diferentes estreses abióticos en postcosecha
AU - Fuentealba, Claudia
AU - Pedreschi, Romina
AU - Hernández, Ignacia
AU - Saavedra, Jorge
N1 - Funding Information:
R. Pedreschi thanks the Fondecyt de Iniciaci?n 11140052 grant from CONICYT, Chile. C. Fuentealba thanks the post-doctoral grant of VRIEA of Pontificia Universidad Cat?lica de Valpara?so (Chile).
Publisher Copyright:
© 2016, Pontificia Universidad Catolica de Chile, Facultad de Agronomia e Ingenieria Forestal. All rights reserved.
PY - 2016
Y1 - 2016
N2 - Hass avocado (Persea americana Mill.) is marketed worldwide. Due to its complex physiology, a wide variability in postharvest ripening can be observed, i.e., heterogeneity in the number of days to reach edible ripeness. There is a need for a simple and objective method for evaluating the efficacy of postharvest treatments in the reduction of this postharvest ripening heterogeneity given the high demand of import countries for consistent quality and product homogeneity. Therefore, the aim of this study was to compare the appropriateness of different statistical methods used to evaluate this ripening heterogeneity. Bartlett’s, Cochran’s, Levene’s homogeneity of variance tests were applied to different treatments. In addition, a multiple comparisons test of squared residuals (parametric and non-parametric) was applied. The classical statistical approaches (Bartlett’s, Cochran’s and Levene’s tests) showed similar results as the multiple comparisons test of squared residuals only when one treatment and large sample sizes (n=100) were evaluated. All statistical methods were able to detect significant differences in ripening heterogeneity from growers and storage conditions. The multiple comparisons test of squared residuals was the most suitable method for multifactorial experiments and small sample sizes (n=30) compared to the classical approaches, which increased the probability of obtaining false positives or a type I error.
AB - Hass avocado (Persea americana Mill.) is marketed worldwide. Due to its complex physiology, a wide variability in postharvest ripening can be observed, i.e., heterogeneity in the number of days to reach edible ripeness. There is a need for a simple and objective method for evaluating the efficacy of postharvest treatments in the reduction of this postharvest ripening heterogeneity given the high demand of import countries for consistent quality and product homogeneity. Therefore, the aim of this study was to compare the appropriateness of different statistical methods used to evaluate this ripening heterogeneity. Bartlett’s, Cochran’s, Levene’s homogeneity of variance tests were applied to different treatments. In addition, a multiple comparisons test of squared residuals (parametric and non-parametric) was applied. The classical statistical approaches (Bartlett’s, Cochran’s and Levene’s tests) showed similar results as the multiple comparisons test of squared residuals only when one treatment and large sample sizes (n=100) were evaluated. All statistical methods were able to detect significant differences in ripening heterogeneity from growers and storage conditions. The multiple comparisons test of squared residuals was the most suitable method for multifactorial experiments and small sample sizes (n=30) compared to the classical approaches, which increased the probability of obtaining false positives or a type I error.
KW - Avocados
KW - Heterogeneity
KW - Multiple comparison
KW - Ripening
KW - Standard deviation
UR - http://www.scopus.com/inward/record.url?scp=85011898438&partnerID=8YFLogxK
U2 - 10.4067/S0718-16202016000300002
DO - 10.4067/S0718-16202016000300002
M3 - Article
AN - SCOPUS:85011898438
SN - 0304-5609
VL - 43
SP - 356
EP - 365
JO - Ciencia e Investigacion Agraria
JF - Ciencia e Investigacion Agraria
IS - 3
ER -