Conditions on unimodality and logconcavity for densities of coherent systems with an application to Bernstein operators

Autor: Tomasz Rychlik, Marco Burkschat, Mariusz Bieniek
Rok vydání: 2018
Předmět:
Zdroj: Journal of Mathematical Analysis and Applications. 467:863-873
ISSN: 0022-247X
DOI: 10.1016/j.jmaa.2018.07.054
Popis: In this note, the distribution of the lifetime of a coherent system with independent and identically distributed component lifetimes is considered. Conditions yielding unimodality or logconcavity of the density function of the system lifetime are obtained. In the conditions, only assumptions on the density function of the components and on the signature of the system are imposed. The results are illustrated with several examples. Additionally, a problem on preservation of logconcavity under the classical Bernstein operator is solved.
Databáze: OpenAIRE