Background: One of the factors that can improve self-concept and performance of staff is professional maturity. Professional maturity can also solve the problems of self-concept. The purpose of this paper was to identify the relationship between the dimensions of self-concept and professional maturity.   Materials and Methods: This relative applicable study was ...

We have studied the effects of range and distribution of data on product moment and rank correlation coefficients when deviation from a linear relationship was due solely to experimentally produced random error. All correlation coefficients (Pearson r, Spearman rho, and Kendall tau) were markedly influenced by the range of the data, and, for the rank correlation coefficients, the effect of rang...

introduction: in the current study, we compared h5-index provided by google scholar (gs), impact factor (if) provided by web of sciences (wos), and scimago journal rank indicator (sjr) provided by scopus for quality assessment of nuclear medicine journals. methods: 2013 h5-index, 2012 if, and 2011 sjr of nuclear medicine journals were extracted from their publishers namely gs, wos, and scopus....

Measures of rank correlation are commonly used in statistics to capture the degree of concordance between two orderings of the same set of items. Standard measures like Kendall’s tau and Spearman’s rho coefficient put equal emphasis on each position of a ranking. Yet, motivated by applications in which some of the positions (typically those on the top) are more important than others, a few weig...

In this paper, we aim at finding a nearest correlation matrix to a given symmetric matrix, measured by the componentwise weighted Frobenius norm, with a prescribed rank and bound constraints on its correlations. This is in general a non-convex and difficult problem due to the presence of the rank constraint. To deal with this difficulty, we first consider a penalized version of this problem and...

Spearman’s rank correlation coefficient is a nonparametric (distribution-free) rank statistic proposed by Charles Spearman as a measure of the strength of an association between two variables. It is a measure of a monotone association that is used when the distribution of data makes Pearson’s correlation coefficient undesirable or misleading. Spearman’s coefficient is not a measure of the linea...

The asymptotic variance and distribution of Spearman's rank correlation have previously been known only under independence. For variables with finite support, the population version of Spearman's rank correlation has been derived. Using this result, we show convergence to a normal distribution irrespectively of dependence, and derive the asymptotic variance. A small simulation study indicates t...

Methods for the approximation of 2D discrete convolution operations are derived for the case when a low-rank approximation of one of the input matrices is available. Algorithms based on explicit computation and on the Fast Fourier Transform are described. Applications to the computation of cross-correlation and autocorrelation are discussed. Both theory and numerical experiments show that the u...