Provider: Ingenta Connect
Database: Ingenta Connect
Content: application/x-research-info-systems
TY - ABST
AU - Buford, M. A.
AU - Hafley, W. L.
TI - Probability Distributions as Models for Mortality
JO - Forest Science
PY - 1985-06-01T00:00:00///
VL - 31
IS - 2
SP - 331
EP - 341
KW - gamma distribution
KW - Weibull distribution
KW - Richards function
KW - Negative binomial distribution
N2 - The necessary attributes for a mortality model for an even-aged forest stand are stated. The Weibull distribution, the gamma distribution, and the negative binomial distribution are proposed based on their previous use in failure research and as mortality models. A distribution derived from the Richards generalization of the von Bertalanffy growth equation is proposed. The four functions are examined mathematically and empirically using data from a loblolly pine spacing study to determine their usefulness as mortality models. The negative binomial distribution and its continuous analog, the gamma distribution, show instability under right-censoring and are computationally difficult. The Weibull distribution shows extreme instability under right-censoring due to constraints on the location of the inflection points of its probability density function, limiting its value as a mortality model. The distribution derived from the Richards generalization of the von Bertalanffy function is stable under right-censoring, shows no constraints on assumable shapes, and is computationally simple. Forest Sci. 31:331-341.
UR - http://www.ingentaconnect.com/content/saf/fs/1985/00000031/00000002/art00011
ER -