The Durbin-Wu-Hausman (DWH) test is a commonly used test for endogeneity in instrumental variables (IV) regression. Unfortunately, the DWH test depends, among other things, on assuming all the instruments are valid, a rarity in practice. In this paper, we show that the DWH test often has distorted size even if one IV is invalid. Also, the DWH test may have low power when many, possibly high dim...

This paper investigates the capital market reaction to first detection of COVID-19 in Bangladesh. Using a sample 314 listed firms Dhaka stock Exchange (DSE), this study employed event methodology (ESM) find any abnormal return (AR) associated announcement. Three different models namely mean-adjusted return, market-adjusted and model have been used calculate test statistical significance using b...

We propose a new method for simulating a Gaussian process, whose spectrum diverges at one or multiple frequencies in 0; 1 2 ] (not necessarily at zero). The method utilizes a generalization of the discrete wavelet transform, the discrete wavelet packet transform (DWPT), and only requires explicit knowledge of the spectral density function of the process { not its autocovariance sequence. An ort...

Durbin (1992) derived a convergent series for the density of the first passage time of a Weiner process to a curved boundary. We show that the successive partial sums of this series can be expressed as the iterates of the standard substitution method for solving an integral equation. The calculation is thus simpler than it first appears. We also show that, under a certain condition, the series ...

knowledge management, in the wisdom and knowledge-based era, has been in organizations' priority, and knowledge is considered as an organizational capital, and its management enjoys a growing importance. this paper has been written with the aim of reviewing the state of knowledge management underlying factors including organizational culture, information technology and knowledge processes ...

Vitamin D may inhibit the development and progression of a wide spectrum of cancers. We investigated the associations of surgery season and vitamin D intake with recurrence-free survival (RFS) and overall survival in 456 early-stage non-small cell lung cancer patients. The data were analyzed using log-rank test and Cox proportional hazards models. The median (range) follow-up time was 71 (0.1-1...

BACKGROUND AIB1 (SRC-3) is an estrogen receptor (ER) coactivator that, when overexpressed in cultured cells, can reduce the antagonist activity of tamoxifen-bound ERs. Signaling through the HER-2 receptor pathway activates AIB1 by phosphorylation. To determine whether high AIB1 expression alone or together with HER-2 reduces the effectiveness of tamoxifen in breast cancer patients, we quantifie...

OBJECTIVE To investigate a possible association between retinal vein occlusion (RVO) and an increased risk of developing acute myocardial infarction (AMI). DESIGN A population-based retrospective cohort study using the entire population of the Taiwan National Health Insurance Research Database (NHIRD) from 1st January, 2001 to 31st December, 2013. METHODS A total of 37921 subjects with RVO ...

MOTIVATION Microarray technology emerges as a powerful tool in life science. One major application of microarray technology is to identify differentially expressed genes under various conditions. Currently, the statistical methods to analyze microarray data are generally unsatisfactory, mainly due to the lack of understanding of the distribution and error structure of microarray data. RESULTS...

MOTIVATION AND RESULTS Durbin et al. (2002), Huber et al. (2002) and Munson (2001) independently introduced a family of transformations (the generalized-log family) which stabilizes the variance of microarray data up to the first order. We introduce a method for estimating the transformation parameter in tandem with a linear model based on the procedure outlined in Box and Cox (1964). We also d...