bubbles in asset prices have fascinated researchers in finance. identify asset bubbles, by circumstances, on the stock market has been a growing number of research theoretical and empirical. on a theoretical level, it was assumed that the price dynamics reflect irrational behavior of economic agents and, therefore, should be excluded from a deal with the truly rational economic agents burmeiste...

It is extremely difficult to predict the initiation time of cracking due to a large time spread in most cracking experiments. Thus, probabilistic models, such as the Weibull distribution, are usually employed to model the initiation time of cracking. Therefore, the parameters of the Weibull distribution are estimated from data collected from a cracking test. However, although the development of...

We propose the Weibull negative binomial distribution that is a quite flexible model to analyze positive data, and includes as special submodels the Weibull, Weibull Poisson and Weibull geometric distributions. Some of its structural properties follow from the fact that its density function can be expressed as a mixture of Weibull densities. We provide explicit expressions for moments, generati...

A new lifetime distribution capable of modeling a bathtub-shaped hazard-rate function is proposed. The proposed model is derived as a limiting case of the Beta Integrated Model and has both the Weibull distribution and Type I extreme value distribution as special cases. The model can be considered as another useful 3-parameter generalization of the Weibull distribution. An advantage of the mode...

Nowadays, the search for a distribution capable of modeling the probability density function (PDF) of irradiance data under all conditions of atmospheric turbulence in the presence of aperture averaging still continues. Here, a family of PDFs alternative to the widely accepted Log-Normal and Gamma-Gamma distributions is proposed to model the PDF of the received optical power in free-space optic...

This study aims to compare the predictive capability of two popular software reliability growth models (SRGM), say exponential growth and inflection S-shaped growth models. We first review the exponentiated Weibull (EW) testing-effort functions and discuss exponential type and inflection S-shaped type SRGM with EW testing-effort. We then analyzed the actual data applications and compare the pre...

the data set employed in this study was comprised of a number of 6,800 records of lamb’s longevity and their survival rate, collected from 1989 through 2009, from the lori-bakhtiari experimental flock at the shooli station in shahrekord, iran. the data were analyzed using linear models and proportional hazard models with weibull function. these models included fixed factors and direct additive ...

the hydrothermal time models have been widely applied to describe the germination responses of seeds to temperature and water potential. in this study, three hydrothermal time models developed on the basis of different statistical distributions (normal, weibull and gumbel) were compared to describe the phalaris minor seed germination. results showed that gumbel (aicc=-762.8) and weibull (aicc=-...