قارن الطرق

	نموذج العائق لبيانات العد	انحدار ذي الحدين السلبي
المجال	الإحصاء	الاقتصاد القياسي
العائلة	Regression model	Regression model
سنة النشأة	1986	2011
صاحب الطريقة	Mullahy	Hilbe (textbook treatment); generalized linear model framework
النوع	Two-part count model	Generalized linear model for count data
المصدر التأسيسي	Mullahy, J. (1986). Specification and Testing of Some Modified Count Data Models. Journal of Econometrics, 33(3), 341–365.	Hilbe, J. M. (2011). Negative Binomial Regression (2nd ed.). Cambridge University Press.
الأسماء البديلة	hurdle count model, two-part count model, zero-truncated count model, Engel Modeli (Hurdle Model)	NB regression, NB2 regression, negatif binom regresyonu
ذات صلة	5	4
الملخص	The hurdle model is a two-part count-data model introduced by Mullahy (1986). A first stage models the binary choice of crossing a hurdle (a zero versus a non-zero count), and a second stage models the strictly positive counts with a zero-truncated distribution such as a zero-truncated Poisson or negative binomial.	Negative Binomial Regression is a generalized linear model for count outcomes that extends Poisson regression to handle overdispersion, where the variance of the counts exceeds their mean. Developed in the GLM tradition and treated in depth by Hilbe (2011), it adds a dispersion parameter so that inference stays valid when Poisson would understate the spread of the data.