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Finite Poisson mixtures can be used in a variety of real applications to describe count data as they can describe situations where overdispersion relative to the simple Poisson model is present. They also admit a natural interpretation: the entire population is a mixture of k subpopulations each...
Persistent link: https://www.econbiz.de/10012987504
Integer valued time series are useful models for describing dependence structures over time for count data for which classical time series models are inappropriate. Such models have been used for a variety of applications. Difficulties arise in attempting to estimate the parameters via maximum...
Persistent link: https://www.econbiz.de/10012987505
In the statistical literature on the study of the capability of processes through the use of indices, Cpm introduced bya Chan et al appears to have been one of the most widely used capability indices and its estimation has attracted much interest. In this article, a new method for constructing...
Persistent link: https://www.econbiz.de/10012987513
In this article several formulae for the approximation of the critical values for tests on the actual values of the process capability indices CPL, CPU, and Cpk are provided. These formulae are based on different approximations of the percentiles of the noncentral t distribution and their...
Persistent link: https://www.econbiz.de/10012987515
In the statistical literature on the study of the capability of processes through the use of indices, Cpm appears to have been one of the most widely used capability indices and its estimation has attracted much interest. In this article, a new method for constructing approximate confidence...
Persistent link: https://www.econbiz.de/10012987519
A number of single ARCH model-based methods of predicting volatility are compared to Degiannakis and Xekalaki's (2005) poly-model standardized prediction error criterion (SPEC) algorithm method in terms of profits from trading actual options of the S&P500 index returns. The results show that...
Persistent link: https://www.econbiz.de/10012987544
A Bayesian technique for assessing the posterior probability that the proportion of conformance of a normally distributed process exceeds a particular value is suggested. Both exact and approximate formulae for the assessment of this probability are derived
Persistent link: https://www.econbiz.de/10012987553
The triangular distribution, although simpler than the beta distribution both for mathematical treatment and for natural interpretation, has not been widely used in the literature as a modelling tool. Applications of this distribution as an alternative to the beta distribution appear to be...
Persistent link: https://www.econbiz.de/10012987567
The use of principal component analysis in measuring the capability of a multivariate process is an issue initially considered by Wang and Chen (1998). In this article, we extend their initial idea by proposing new indices that can be used in situations where the specification limits of the...
Persistent link: https://www.econbiz.de/10012987569
In statistical modeling contexts, the use of one-step-ahead prediction errors for testing hypotheses on the forecasting ability of an assumed model has been widely considered (see, e.g., Xekalaki et al. (2003, in Stochastic Musings, J.Panaretos (ed.), Laurence Erlbaum), Degiannakis and Xekalaki...
Persistent link: https://www.econbiz.de/10014062060