1,531 research outputs found
Extended Lindley Poisson Distribution
The Extended Lindley Poisson (ELP) distribution which is an extension of the extended Lindley distribution [2] is introduced and its properties are explored. This new distribution represents a more flexible model for the lifetime data. Some statistical properties of the proposed distribution including the shapes of the density, hazard rate functions, moments, Bonferroni and Lorenz curves are explored. Entropy measures and the distribution of the order statistics are given. The maximum likelihood estimation technique is used to estimate the model parameters and a simulation study is conducted to investigate the performance of the maximum likelihood estimates. Finally, we present applications of the model with a real data set to illustrate the usefulness of the proposed distribution
Kumaraswamy Lindley-Poisson Distribution: Theory and Applications
The Kumaraswamy Lindley-Poisson (KLP) distribution which is an extension of the Lindley-Poisson Distribution [21] is introduced and its properties are explored. This new distribution represents a more flexible model for the lifetime data. Some statistical properties of the proposed distribution including the shapes of the density and hazard rate functions are explored. Moments, entropy measures and the distribution of the order statistics are given. The maximum likelihood estimation technique is used to estimate the model parameters and a simulation study is conducted to investigate the performance of the maximum likelihood estimates. Finally some applications of the model with real data sets are presented to illustrate the usefulness of the proposed distribution
The Beta Lindley-Poisson Distribution with Applications
The beta Lindley-Poisson (BLP) distribution which is an extension of the Lindley-Poisson Distribution is introduced and its properties are explored. This new distribution represents a more flexible model for the lifetime data. Some statistical properties of the proposed distribution including the expansion of the density function, hazard rate function, moments and moment generating function, skewness and kurtosis are explored. Renyi entropy and the distribution of the order statistics are given. The maximum likelihood estimation technique is used to estimate the model parameters and finally applications of the model to real data sets are presented for the illustration of the usefulness of the proposed distribution
A New Class of Generalized Power Lindley Distribution with Applications to Lifetime Data
A new class of distribution called the beta-exponentiated power Lindley (BEPL) distribution is proposed. This class of distributions includes the Lindley (L), exponentiated Lindley (EL), power Lindley (PL), exponentiated power Lindley (EPL), beta-exponentiated Lindley (BEL), beta-Lindley (BL), and beta-power Lindley distributions (BPL) as special cases. Expansion of the density of BEPL distribution is obtained. Some mathematical properties of the new distribution including hazard function, reverse hazard function, moments, mean deviations, Lorenz and Bonferroni curves are presented. Entropy measures and the distribution of the order statistics are given. The maximum likelihood estimation technique is used to estimate the model parameters. Finally, real data examples are discussed to illustrate the usefulness and applicability of the proposed distribution
The Log-Logistic Weibull Distribution with Applications to Lifetime Data
In this paper, a new generalized distribution called the log-logistic Weibull (LLoGW) distribution is developed and presented. This distribution contain the log-logistic Rayleigh (LLoGR), log-logistic exponential (LLoGE) and log-logistic (LLoG) distributions as special cases. The structural properties of the distribution including the hazard function, reverse hazard function, quantile function, probability weighted moments, moments, conditional moments, mean deviations, Bonferroni and Lorenz curves, distribution of order statistics, L-moments and Renyi entropy are derived. Method of maximum likelihood is used to estimate the parameters of this new distribution. A simulation study to examine the bias, mean square error of the maximum likelihood estimators and width of the condence intervals for each parameter is presented. Finally, real data examples are presented to illustrate the usefulness and applicability of the model
Dagum-Poisson Distribution: Model, Properties and Application
A new four parameter distribution called the Dagum-Poisson (DP) distribution is introduced and studied. This distribution is obtained by compounding Dagum and Poisson distributions. The structural properties of the new distribution are discussed, including explicit algebraic formulas for its survival and hazard functions, quantile function, moments, moment generating function, conditional moments, mean and median deviations, Bonferroni and Lorenz curves, distribution of order statistics and R\\u27enyi entropy. Method of maximum likelihood is used for estimating the model parameters. A Monte Carlo simulation study is conducted to examine the bias, mean square error of the maximum likelihood estimators and width of the confidence interval for each parameter. A real data set is used to illustrate the usefulness, applicability, importance and flexibility of the new distribution
MedZIM: Mediation analysis for Zero-Inflated Mediators with applications to microbiome data
The human microbiome can contribute to the pathogenesis of many complex
diseases such as cancer and Alzheimer's disease by mediating disease-leading
causal pathways. However, standard mediation analysis is not adequate in the
context of microbiome data due to the excessive number of zero values in the
data. Zero-valued sequencing reads, commonly observed in microbiome studies,
arise for technical and/or biological reasons. Mediation analysis approaches
for analyzing zero-inflated mediators are still lacking largely because of
challenges raised by the zero-inflated data structure: (a) disentangling the
mediation effect induced by the point mass at zero; and (b) identifying the
observed zero-valued data points that are actually not zero (i.e., false
zeros). We develop a novel mediation analysis method under the
potential-outcomes framework to fill this gap. We show that the mediation
effect of the microbiome can be decomposed into two components that are
inherent to the two-part nature of zero-inflated distributions. The first
component corresponds to the mediation effect attributable to a unit-change
over the positive relative abundance and the second component corresponds to
the mediation effect attributable to discrete binary change of the mediator
from zero to a non-zero state. With probabilistic models to account for
observing zeros, we also address the challenge with false zeros. A
comprehensive simulation study and the applications in two real microbiome
studies demonstrate that our approach outperforms existing mediation analysis
approaches.Comment: Corresponding: Zhigang L
A matrix for the qualitative evaluation of nursing tasks
Aims
To formulate a model for patient–nurse interaction; to compile a comprehensive list of nursing tasks on hospital wards; and to construct a nursing tasks demand matrix.
Background
The physical demands associated with nursing profession are of growing interest among researchers. Yet, it is the complexity of nursing tasks that defines the demands of ward nurses’ role. This study explores nursing tasks, based on patient–nurse interaction on hospital wards.
Methods
Extant literature was reviewed to formulate a patient–nurse interaction model. Twenty ward nurses were interviewed to compile a list of nursing tasks. These nursing tasks were mapped against the patient–nurse interaction model.
Results
A patient–nurse interaction model was created, consisting of: (1) patient care, (2) patient surveillance and (3) patient support. Twenty-three nursing tasks were identified. The nursing tasks demand matrix was constructed.
Conclusions
Ward managers may use a nursing tasks demand matrix to determine the demands of nursing tasks on ward nurses.
Implications for Nursing Management
While many studies have explored either the physical or the psychosocial aspects of nursing tasks separately, this study suggests that the physicality of nursing tasks must be evaluated in tandem with their complexity. Ward managers may take a holistic approach to nursing tasks evaluation by using a nursing tasks demand matrix
Multimodal analysis of ocular inflammation using the endotoxin-induced uveitis mouse model
Endotoxin-induced uveitis (EIU) in rodents is a model of acute Toll-like receptor 4 (TLR4)-mediated organ inflammation, and has been used to model human anterior uveitis, examine leukocyte trafficking and test novel anti-inflammatory therapeutics. Wider adoption has been limited by the requirement for manual, non-specific, cell-count scoring of histological sections from each eye as a measure of disease severity. Here, we describe a comprehensive and efficient technique that uses ocular dissection and multimodal tissue analysis. This allows matched disease scoring by multicolour flow cytometric analysis of the inflammatory infiltrate, protein analysis on ocular supernatants and qPCR on remnant tissues of the same eye. Dynamic changes in cell populations could be identified and mapped to chemokine and cytokine changes over the course of the model. To validate the technique, dose-responsive suppression of leukocyte infiltration by recombinant interleukin-10 was demonstrated, as well as selective suppression of the monocyte (CD11b+Ly6C+) infiltrate, in mice deficient for either Ccl2 or Ccr2. Optical coherence tomography (OCT) was used for the first time in this model to allow in vivo imaging of infiltrating vitreous cells, and correlated with CD11b+Ly6G+ counts to provide another unique measure of cell populations in the ocular tissue. Multimodal tissue analysis of EIU is proposed as a new standard to improve and broaden the application of this model
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