A longitudinal model for shapes through triangulation

AStA Advances in Statistical Analysis - It is known that the shapes of planar triangles can be represented by a set of points on the surface of the unit sphere. On the other hand, most of the...     

Bayesian prediction for progressively censored data from the Burr model

Received: August 14, 2000; revised version: April 23, 2001     

Bayesian Prediction for Progressively Type-II Censored Data from the Rayleigh Model

ABSTRACT

The Rayleigh distribution is proposed to be the underlying model from which observables are to be predicted by using Bayesian approach. Progressively Type-II censored data from the Rayleigh distribution is considered and the two-sample prediction technique is used. Numerical computations and a simulation are given to illustrate the performance of the procedures.     

The use of simple reparameterizations to improve the efficiency of Markov chain Monte Carlo estimation for multilevel models with applications to discrete time survival models

Summary.  We consider the application of Markov chain Monte Carlo (MCMC) estimation methods to random-effects models and in particular the family of discrete time survival models. Survival models can be used in many situations in the medical and social sciences and we illustrate their use through two examples that differ in terms of both substantive area and data structure. A multilevel discrete time survival analysis involves expanding the data set so that the model can be cast as a standard multilevel binary response model. For such models it has been shown that MCMC methods have advantages in terms of reducing estimate bias. However, the data expansion results in very large data sets for which MCMC estimation is often slow and can produce chains that exhibit poor mixing. Any way of improving the mixing will result in both speeding up the methods and more confidence in the estimates that are produced. The MCMC methodological literature is full of alternative algorithms designed to improve mixing of chains and we describe three reparameterization techniques that are easy to implement in available software. We consider two examples of multilevel survival analysis: incidence of mastitis in dairy cattle and contraceptive use dynamics in Indonesia. For each application we show where the reparameterization techniques can be used and assess their performance.     

Does Gender Diversity Affect Workplace Happiness for Academics? The Role of Diversity Management and Organizational Inclusion

Public Organization Review - The author investigated the relationship between gender diversity and organizational inclusion and moved forward to examine whether gender diversity, diversity...     

MINIMAX ESTIMATION OF A MULTIVARIATE NORMAL MEAN UNDER A CONVEX LOSS FUNCTION

Let X = (X₁, - X_p)prime; ˜ N_p (μ, Σ) where μ= (μ₁, -, μ_p)' and Σ= diag (Σ²₁, -, Σ²_p) are both unknown and p3. Let (n_i - 2) w_i/Σ²_i! X²_ni, independent. of w_i (I ≠ j = 1, -, p). Assume that (w₁, -, w_p) and X are independent. Define W = diag (w₁, -, w_p) and ¶ X ¶²_w= X'W^-1Q^-1W^-1X where Q = diag (q₁, -,n q_p), q_i > 0, i = 1, -, p. In this paper, the minimax estimator of Berger & Bock (1976), given by δ (X, W) = [I_p - r(X, W) ¶ X ¶^-2_w Q^-1W^-1] X, is shown to be minimax relative to the convex loss (δ - μ)'[αQ + (1 - α) Σ^-1] δ - μ)/C, where C =α tr (Σ) + (1 - α)p and 0 α 1, under certain conditions on r(X, W). This generalizes the above mentioned result of Berger & Bock.     

Pre- versus post-crisis central banking in Qatar

In the years before the global financial crisis of 2008–2010, Qatar experienced a huge build-up of liquidity surplus in the banking system, mainly driven by surging net capital inflows. This paper identifies various sources of interbank liquidity in Qatar and discusses the various implications of structural primary liquidity surplus for the money market in particular and the economy at large. The paper attempts to evaluate the Qatar Central Bank policy making and conduct during the pre- and post-crisis periods within a framework of the Austrian monetary overinvestment theories, and concludes that the central bank had forcibly committed several forced monetary policy mistakes, which resulted in a breakdown in the interest rate channel of the monetary policy transmission mechanism. This led to the inability of the central bank to control the interbank interest rate and to an accelerating inflation rate during the pre-crisis years. In contrast, a dramatic change in the central bank's monetary policy framework and a deliberate monetary policy mistake on behalf of the central bank resulted in a restoration of the interest rate channel of the monetary policy transmission mechanism, stabilization of the interbank interest rate close to the central bank's policy rate and a sharp deceleration in the inflation rate in the post-crisis period. The paper concludes by offering brief policy recommendations.     

A new non parametric estimator for Pdf based on inverse gamma distribution

ABSTRACT

The non parametric approach is considered to estimate probability density function (Pdf) which is supported on(0, ∞). This approach is the inverse gamma kernel. We show that it has same properties as gamma, reciprocal inverse Gaussian, and inverse Gaussian kernels such that it is free of the boundary bias, non negative, and it achieves the optimal rate of convergence for the mean integrated squared error. Also some properties of the estimator were established such as bias and variance. Comparison of the bandwidth selection methods for inverse gamma kernel estimation of Pdf is done.