Using male/female and Caucasian/African American comparison groups, this study examined the practical ramifications of using two IRT-based analytic methods, DFIT and the Likelihood Ratio Test (LRT), in assessing the measurement invariance of a 21-item leadership development scale under ten sample size conditions (e.g., 200, 500, & 1000). In nine of ten conditions, the LRT identified multiple it...

It has been shown that in optical communication systems with detectors that have a multiplicative noise component, the bit error rate (BER) can be improved by orders of magnitude through the use of a thresholding scheme based on a likelihood ratio test (LRT) instead of a matched filter [1]. An LRT detection scheme of this type has been derived previously for optically encoded Manchester data [1...

The selective pressure at the protein level is usually measured by the nonsynonymous/synonymous rate ratio (omega = dN/dS), with omega < 1, omega = 1, and omega > 1 indicating purifying (or negative) selection, neutral evolution, and diversifying (or positive) selection, respectively. The omega ratio is commonly calculated as an average over sites. As every functional protein has some amino aci...

We previously demonstrated that blockade of immune suppressive CTLA-4 resulted in tumor growth delay when combined with chemotherapy in murine mesothelioma. Tumor-infiltrating T cells (TIT) after local radiotherapy (LRT) play critical roles in abscopal effect against cancer. We attempt to improve the local and abscopal effect by modulating T cell immunity with systemic blockade of CTLA-4 signal...

BACKGROUND AND PURPOSE An extradurally located cavernous sinus dural arteriovenous fistula (CSDAVF) exhibits different clinical behavior from other dural arteriovenous fistulas (DAVFs) located between 2 dural leaves. The aim of this study is to define angiographic types of CSDAVF associated with presenting symptom (Sx) and venous drainage patterns. METHODS CSDAVFs during a mean of 23-month fo...

UNLABELLED We propose a likelihood ratio test (LRT) with Bartlett correction in order to identify Granger causality between sets of time series gene expression data. The performance of the proposed test is compared to a previously published bootstrap-based approach. LRT is shown to be significantly faster and statistically powerful even within non-Normal distributions. An R package named gGrang...

We present a framework for the analysis of frame synchronization based on Synchronization Words (SWs), where the detection is based on the common sequential algorithm: the received samples are observed over a window of length equal to the SW; over this window a metric (e.g. correlation) is computed; a SW is declared if the computed metric is greater than a proper threshold, otherwise the observ...

In this paper, we consider the problem of testing the equality of multivariate normal populations when the data set has missing observations with a two-step monotone pattern. The likelihood ratio test (LRT) statistic for the simultaneous testing of the mean vectors and the covariance matrices is given under the condition of two-step monotone missing data. An approximate modified likelihood rati...

In the United States, Light Rail Transit (LRT) systems have become a popular transportation alternative. Minnesota built its first light rail system in 2004 with the Hiawatha Line and additional projects are underway in the Minneapolis and St. Paul area. While light rail systems are attractive to commuters, they are expensive to construct and careful planning is ongoing to ensure their effectiv...

This paper investigates the statistical detection of JSteg steganography. The approach is based on a statistical model of discrete cosine transformation (DCT) coefficients challenging the usual assumption that among a subband all the coefficients are independent and identically distributed (i. i. d. ). The hidden information-detection problem is cast in the framework of hypothesis testing theor...