Auxiliary information is mostly used together with study variable to enhance efficiency of estimators for population mean, total and variance. Thompson introduced adaptive cluster sampling as an appropriate sampling scheme for rare and clustered populations. In present article, difference-type and difference-cum-exponential-ratio-type estimators are presented utilizing two auxiliary variables for estimation of general parameter under stratified adaptive cluster sampling. Proposed estimators utilize auxiliary information in terms of ranks, variances and means of auxiliary variables in h th stratum. Expressions for bias and mean square error of proposed estimators are derived using first order of approximation. Numerical study is conducted to evaluate the performance of proposed estimators.

The estimators utilise information on two auxiliary variables about population parameters of auxiliary variables. The proposed estimators for general parameter can be used to estimate and variance of the variable of interest. The bias and mean square error equations for the proposed estimators are derived in all three situations under adaptive cluster sampling. Two different populations are used for numerical illustration.

Recently, El-Sherpieny et al., (2020), suggested Type-II hybrid censoring method for parametric estimation of Lomax distribution (LD) without due regard being given to the choice of priors and posterior risk associated with the model. This paper fills this gap and derived the new LD model with minimum posterior risk for the selection of priors. It derives a closed form expression for Bayes estimates and posterior risks using square error loss function (SELF), weighted loss function (WLF), quadratic loss function (QLF) and DeGroot loss function (DLF). Prior predictive approach is used to elicit the hyperparameters of mixture model. Analysis of Bayes estimates and posterior risks is presented in terms of sample size (n), mixing proportion ( p ) and censoring rate ( t 0 ), with the help of simulation study. Usefulness of the model is demonstrated on applying it to simulated and real-life data which show promising results in terms of better estimation and risk reduction.

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Objective: To see the efficacy of rapid color test for the sensitivity of ceftriaxone against clinical isolates of Salmonella Typhi. Methods: This descriptive cross sectional study was carried out at the department of Microbiology, Pakistan Navy Ship (PNS) Shifa Hospital, Karachi from Nov 2018 through April 2019.We tested 97 clinical isolates of Salmonella Typhi by this rapid color test. All the isolates were also test by conventional disc diffusion method and MICs by Vitek-2 system. Results: Out of these isolates, 83 were ceftriaxone resistant while 14 isolates were ceftriaxone sensitive. Sensitivity and specificity of rapid color test were 100% when compared with results of disc diffusion, E-test and Vitek 2 system. All the results were readable within 2 hours on color test. Conclusion: This color test is rapid, accurate and inexpensive and can be used as a screening test for ceftriaxone resistance in typhoid endemic areas. Keywords: Ceftriaxone; drug resistance; meropenem Continuous...