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In this paper, we introduce a new extension of the power Lindley distribution, called the exponentiated generalized power Lindley distribution. Several mathematical properties of the new model such as the shapes of the density and hazard rate functions, the quantile function, moments, mean deviations, Bonferroni and Lorenz curves and order statistics are derived.Moreover, we discuss the parameter estimation of the new distribution using the maximum likelihood and diagonally weighted least squares methods. A simulation study is performed to evaluate the estimators. We use two real data sets to illustrate the applicability of the new model. Empirical findings show that the proposed model provides better fits than some other well-known extensions of Lindley distributions.  相似文献   
3.
Chemical looping combustion (CLC) is a novel method of carbon capture and sequestration. It facilitates CO2 capture by lower energy penalties compared with other methods in this category. The major challenges encountered in CLC are oxygen carrier, reactor and fuel-type selection. A proper combination of these factors is required for an efficient CLC. There have been several studies with regard to oxygen carriers applicable to these processes: novel oxygen carriers, single perovskites and potential oxygen carriers, double perovskites, have been investigated for their oxygen capture and release properties in a number of studies. Different kinds of reactors have also been proposed for use in CLC processes. This paper presents information on the materials capable of oxygen storage and release and the different kinds of reactors investigated for CLC in different studies. It has been shown that, although there are several oxygen carriers and reactors with the desired function and efficiency for CLC, there remains the need for further improvement and optimisation in both areas. © 2014 Institute of Chemistry, Slovak Academy of Sciences  相似文献   
4.
We give the cumulative distribution function of $M_n$ , the maximum of a sequence of n observations from a first order moving average. Solutions are first given in terms of repeated integrals and then for the case, where the underlying independent random variables have an absolutely continuous probability density function. When the correlation is positive, $P( M_n \leq x ) \ =\ \sum\limits _{j=1}^{\infty } \beta _{j, x} \ \nu _{j, x}^{n},$ where $\{\nu _{j, x}\}$ are the eigenvalues (singular values) of a Fredholm kernel and $\beta _{j, x}$ are some coefficients determined later. A similar result is given when the correlation is negative. The result is analogous to large deviations expansions for estimates, since the maximum need not be standardized to have a limit. For the continuous case the integral equations for the left and right eigenfunctions are converted to first order linear differential equations. The eigenvalues satisfy an equation of the form $\sum\limits _{i=1}^{\infty } w_i ( \lambda -\theta _i )^{-1}=\lambda -\theta _0$ for certain known weights $\{ w_i\}$ and eigenvalues $\{ \theta _i\}$ of a given matrix. This can be solved by truncating the sum to an increasing number of terms.  相似文献   
5.
Exact expressions are derived for the probability density function, cumulative distribution function and moment properties of the product of N independent Student??s t random variables. A program is provided for computing the associated percentage points. Estimation issues by the methods of moments and maximum likelihood are discussed.  相似文献   
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Simple integral representations are derived for the moments of the absorption time of Kingman’s coalescent Kingman (J Appl Probab 19:27-43, (1982a)). Their computational efficiency versus known representations is established.  相似文献   
7.
Withers and Nadarajah (Stat Pap 51:247–257; 2010) gave simple Edgeworth-type expansions for log densities of univariate estimates whose cumulants satisfy standard expansions. Here, we extend the Edgeworth-type expansions for multivariate estimates with coefficients expressed in terms of Bell polynomials. Their advantage over the usual Edgeworth expansion for the density is that the kth term is a polynomial of degree only k + 2, not 3k. Their advantage over those in Takemura and Takeuchi [Sankhyā, A, 50, 1998, 111-136] is computational efficiency  相似文献   
8.
Without a doubt, the logistic distribution is the most popular statistical model in the social sciences and related areas. Motivated by the importance of products of random variables in these areas, we derive the exact distributions of | X 1 X 2 | and | X 1 X 2 ⋯ X p  | when X m are independent logistic random variables. Tabulations of the associated percentage points are provided and possible extensions discussed.  相似文献   
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Suppose ${\widehat{\theta}_1}$ and ${\widehat{\theta}_2}$ are asymptotically independent non-lattice with a joint second order Edgeworth expansion in n ?1/2. Then the ?? dependency coefficient is $$\alpha \left(\widehat{\theta}_1, \widehat{\theta}_2 \right) = n^{-1/2} C + O \left(n^{-1} \right),$$ where ${C = (4 \pi)^{-1}\exp (-1/2) (\tau^2_1 + \tau^2_2) ^{1/2}}$ for ${\tau_1, \tau_2}$ their joint skewness coefficients.  相似文献   
10.
The known estimation and simulation methods for multivariate t distributions are reviewed. A review of selected applications is also provided. We believe that this review will serve as an important reference and encourage further research activities in the area.  相似文献   
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