The inverse weighted Lindley distribution: Properties,estimation and an application on a failure time data

In this paper a new distribution is proposed. This new model provides more flexibility to modeling data with upside-down bathtub hazard rate function. A significant account of mathematical properties of the new distribution is presented. The maximum likelihood estimators for the parameters in the presence of complete and censored data are presented. Two corrective approaches are considered to derive modified estimators that are bias-free to second order. A numerical simulation is carried out to examine the efficiency of the bias correction. Finally, an application using a real data set is presented in order to illustrate our proposed distribution.     

A strange tale

We are going through such challenging times that dealing with reality is sometimes easier through fiction. Therefore, we tell the tale of a faraway land where poor women — mostly black — who make a living as domestic servants are particularly impacted by the COVID‐19 pandemic. Their abject bodies are part of a form of necropolitics that separates those who must live from those who can die. Their bodies do not matter, as they are perceived as mere working tools. And what sounds like a strange tale is the true reality of millions of women during the pandemic, in a land that is not so far away as it seems.     

Restricted alternatives tests in a bivariate exponential model with covariates

This paper is about the analysis of paired survival data using the exponential bivariate model of Sarkar for the underlying survival times, (X,Y), subject to censoring. Under this parametric model we test parameters in the presence of covariates. We consider first, tests of hypotheses of independence and equality of survival marginals, and second, test of hypotheses of covariate effects and survival superiority of one marginal over the other are considered. For this last question we applied a statistical test based on the Union-intersection principle.     

Transformational leadership and job satisfaction of police officers (carabineros) in Chile: the mediating effects of group identification and work engagement / Liderazgo transformacional y satisfacción laboral en carabineros de Chile: los efectos mediadores de la identificación con el grupo y el work engagement

Abstract

The aim of this paper is to examine the relationship between transformational leadership and work satisfaction, as well as to analyse the mediating role of group identification and work engagement in a police training process at a Chilean professional military institution. The sample was made up of 985 candidates representing all the candidates that joined the units of the country in the different locations. Officers and non-commissioned officers acting as instructors were considered ‘leaders’, while their ‘followers’ were the young candidates in the training period. It was found that all the relevant variables were positively and significantly interrelated, and a model of structural equations revealed that both work engagement and group identification played a mediating role in the relationship between transformational leadership and work satisfaction.     

Markers of unsustainable gambling for early detection of at-risk online gamblers

In this work we propose novel markers for identifying at-risk gamblers based on the concept of sustainability. The first hypothesis here verified is that problematic gamblers oscillate between intervals of increasing wager size followed by rapid drops, probably because they exceed their economic sustainability limits. Due to the non-periodic nature of these fluctuations, the proposed marker detects a certain occurring feature, such as a rapid drop in wager size, over a wide range of fluctuation periods, drop sizes and shapes. The second marker, counting the number of games the gambler is involved in, aims at predicting possible consequences of an exceeding amount of time dedicated to gambling, that ultimately causes social and relational breakdowns. In the experimental phase we demonstrate how the adoption of these markers allows for identifying larger segments of high- and medium-risk gamblers with respect to previous research on actual betting behaviours.     

Testing Covariance Stationarity

In this paper, we show that the widely used stationarity tests such as the Kwiatkowski Phillips, Schmidt, and Shin (KPSS) test have power close to size in the presence of time-varying unconditional variance. We propose a new test as a complement of the existing tests. Monte Carlo experiments show that the proposed test possesses the following characteristics: (i) in the presence of unit root or a structural change in the mean, the proposed test is as powerful as the KPSS and other tests; (ii) in the presence of a changing variance, the traditional tests perform badly whereas the proposed test has high power comparing to the existing tests; (iii) the proposed test has the same size as traditional stationarity tests under the null hypothesis of stationarity. An application to daily observations of return on U.S. Dollar/Euro exchange rate reveals the existence of instability in the unconditional variance when the entire sample is considered, but stability is found in subsamples.     

WHY DO EMERGING ECONOMIES BORROW SHORT TERM?

We argue that one reason why emerging economies borrow short term is that it is cheaper than borrowing long term. This is especially the case during crises, as during these episodes the relative cost of long‐term borrowing increases. We construct a unique database of sovereign bond prices, returns, and issuances at different maturities for 11 emerging economies from 1990 to 2009 and present a set of new stylized facts. On average, these countries pay a higher risk premium on long‐term than on short‐term bonds. During crises, the difference between the two risk premia increases and issuance shifts towards shorter maturities. To illustrate our argument, we present a simple model in which the maturity structure is the outcome of a risk‐sharing problem between an emerging economy subject to rollover crises and risk‐averse international investors.     

Flexibility,endogenous risk,and the protection premium

We introduce two types of protection premia. The unconstrained protection premium, ^u, is the individual's willingness to pay for certain protection efficiency given flexibility to adjust optimally the investment in protection. The constrained protection premium, ^c, measures willingness to pay for certain protection efficiency given no flexibility to adjust the investment in protection. ^u depends on tastes and wealth as well as protection technology whereas ^c depends only on technology. We show that ^c cannot exceed ^u and develop necessary conditions for ^c=^u. Optimal protection for an individual with decision flexibility may be larger or smaller than that desired under no flexibility.Journal Paper No. J-15504 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 3048.