An efficiency comparison of dual ratio and product estimatiors

The present paper investigates the efficiency of the dual ratio estimator under the super population model with uncorrelated errors and a gamma-distributed auxiliary variabble. It is found that the dual ratio estimator is more efficient than the product estimator when the auxiliary variable has a gamma distribution with parameter greater than or equal to one, in the case when the regression is through the origin or when the product of intercept and slope is positive.     

Minimum variance unbiased estimation in a modified power series distribution and some of its applications

In this paper we study the minimum variance unbiased estimation in the modified power series distribution introduced by the author (1974a). Necessary and sufficient conditions for the existence of minimum variance unbiased estimate (MVUE) of the parameter based on sufficient statistics are obtained. These results are, then, applied to obtain MVUE of θ^r (r ≥ 1) for the generalized negative binomial and the decapitated generalized negative binomial distributions (Jain and Consul, 1971). Similar estimates are obtained for the generalized Poisson (Consul and Jain, 1973a) and the generalized logarithmic series distributions (Jain and Gupta, 1973). Several of the well-known results follow trivially from the results obtained here.     

A bound connected with 26 factorial search designs of resolution 3.1

In this paper, we give a lower bound for the number of treatments required

for a plan to be a main effect plus one plan for 2^m (m = 6) factorial experiments, The lower bound problem is important in the event of generating new designs with similar properties or when one wants to study the criteria of optimality for such designs.     

On testing structure of mean vector of compound symmetric gaussian model

In this paper the moments of the likelihood ratio statistic for testing the structure of mean vector of a compound symmetric Gaussian model, have been derived by using the orthogonal transformation of variables. Then the distribution of the test statistic is studied.     

Admissibility of generalized bayes and pitman estimates in the non-regular family

In this paper we have considered the problem of finding admissible estimates for a fairly general class of parametric functions in the so called “non-regular” type of densities Following Karlin s (1958) technique, we have established the ad-missibility of generalized Bayes estimates and Pitman estimates. Some examples are discussed.     

A new behavioural model for fertility schedules

Modelling age-specific fertility rates is of great importance in demography because of their influence on population growth. Although we have a variety of fertility models in the demographic literature, most of them do not have any demographic interpretation for their parameters. It is generally expected that models with behavioural interpretation are more universal than those without any interpretation. Even though the famous Gompertz model has some behavioural interpretation it suffers from other drawbacks. In the present work, we propose a new fertility model, which has its genesis in the generalization of logistic law. The proposed model has good behavioural interpretation, alongside having nice parameter interpretations.     

DIRECTIVE AND NONDIRECTIVE SPOUSAL SUPPORT: DIFFERENTIAL EFFECTS?

In this study we investigated whether the following factors influenced married partners' reactions to spousal support: type of support (directive vs. nondirective); individual differences (gender, depressive symptoms); and dimension along which support was evaluated (level of helpfulness vs. valence of emotional impact). Nondirective support was consistently rated more favorably on the dimension of partner's impact than on the dimension of partner's helpfulness, and this effect was exaggerated for those self-reporting a high level of depressive symptoms. Nonetheless, directive support was provided more frequently than was nondirective support in this sample. Gender differences and complications introduced by partner dysphoria suggest some situations in which directive support may be particularly difficult to provide effectively. Implications for couple therapy are discussed.     

Change point analysis of a Gaussian model

In this paper, the testing and estimation of a single change point in means and variances of a sequence of independent Gaussian normal random variables are studied. The Schwarz Information Criterion, SIC, is used to search for the change point. The unbiased version of the SIC for this change point problem is also derived for the finite sample case. Other properties of the SIC test statistic are given as well. Finally, two examples are given at the end of this paper to illustrate the method proposed, and changes are successfully detected.     

A Class of Estimators of Population Variance Using Auxiliary Information in Sample Surveys

This article advocates the problem of estimating the population variance of the study variable using information on certain known parameters of an auxiliary variable. A class of estimators for population variance using information on an auxiliary variable has been defined. In addition to many estimators, usual unbiased estimator, Isaki's (1983), Upadhyaya and Singh's (1999), and Kadilar and Cingi's (2006) estimators are shown as members of the proposed class of estimators. Asymptotic expressions for bias and mean square error of the proposed class of estimators have been obtained. An empirical study has been carried out to judge the performance of the various estimators of population variance generated from the proposed class of estimators over usual unbiased estimator, Isaki's (1983), Upadhyaya and Singh's (1999) and Kadilar and Cingi's (2006) estimators.     

An advertising effect model

A model of advertising effects has been developed based on a distinction between “persuasion” advertising and “trigger” advertising. The former is designed to induce prospective purchasers to try the product and to establish a “product image”. The latter is aimed at “triggering” a purchase on the part of an individual whose image of the product has already been formed. The distinction has major implications for the type and timing of advertising. The model can be applied to determining an optimum distribution of advertising effort in the introduction of a new product, and the optimum advertising media mix.