Modeling insect-egg data with excess zeros using zero-inflatedregression models.Hacettepe Journal of Mathematics and Statistics. 39(2): 273-282

Abstract

As zero-inflated observations occur very often in studies on plant pro?tection, models taking into account zero-inflated observations are fre?quently required. Especially, zero-inflated observations occur in large numbers for insects whose post-oviposition period lasts long, or that generally lay their eggs during the first days of the oviposition period. For the data used in this study, 1114 (43.84%) of the 2541 observations were zero. In the selection of an appropriate regression model, zero?inflated negative binomial regression was chosen as the best model. In all regression models, the day of laying and the three different hosts were seen to have a significant effect on daily egg numbers (p < 0.01).