摘要:

Rank conditions for identification in structural models are often difficult evaluate. Here we consider simultaneous equation models with measurement error and we show that previously published rank conditions for identification are not well‐suited for evaluation. An alternative rank condition is derived and a computer algebra program is presented that takes care of both the construction and the computation of the rank of the relevant Jacobian matrix. It uses the parameter restrictions as input in order to characterize the identification situation of the individual parameters in the outpu

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01420.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Some characterizations ofa‐unimodal lattice distributions, introduced in Abouammoh (1987,19881, anda‐monotone lattice distributions, introduced in Steutel (1988), are discussed. Convolution and symmetrization ofa‐monotone lattice distributions are also investigated. The characterizations and convolution properties obtained by Abouammoh in this connection are corrected and imp

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01421.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

When studying the stochastic process of mortality related to observed co‐variables in a cohort of subjects followed in time, it is usually assumed that the observed covariables are given, non‐stochastic quantities. In this way one can predict only a subject's survivor function, given certain values of the covariables at baseline. Continuous covariables are assumed to have (approximately) a multivariate Gaussian distribution in a cohort and to evolve with random fluctuation in subjects as a consequence of ageing. Woodbury et al. elaborated a model where this evolution‐diffusion process (called ageing process) can be incorporated and kept in balance by an appropriately modelled mortality selection process, so that the distribution of the covariables in the cohort remains (approximately) Gaussian. The analytical tractability of this model allows one to readily calculate the cohort survivor function as ultimately being epidemiologically more relevant than individual survivo

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01422.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

A random walk {Sn} withSn= (Xl‐ Yl) +…+ (Xn‐Yn) is considered where theXnYnarenon‐negative random variables, theYnare exponentially distributed with rate δ and theXnhave common distribution functionB. It is shown that the expression δ(1 ‐S(x)) for the density of the ascending ladder height distribution of (Sn), which is well‐known for i.i.d.Xn, holds also when theXnform a stationary sequence of not necessarily independent ran

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01423.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Given a random variableXwith finite mean, for each 0

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01424.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

De Vos (1991) claims to have discovered a new example from agricultural field experimentation which shows that a simple robust spatial model may lead to inference and systematic experimental design that outperforms the inference from randomized experiments by far. In this reaction it is shown that: (1) the example is not new; (2) the gains in efficiency are exaggerated due to comparison with an inefficient randomization method; (3) the paper is over‐optimistic with respect to robustness of model‐based methods and throws unjustified doubts on the validity of randomization methods; (4) the choice between randomization methods and model‐based methods depends on the relative importance attached to efficiency and val

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01425.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01426.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0039-0402    

DOI:10.1111/j.1467-9574.1993.tb01427.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY