Fisher transformation ≈ Fisher transformation
View article
Correlation Coefficients: Appropriate Use and Interpretation Open
Correlation in the broadest sense is a measure of an association between variables. In correlated data, the change in the magnitude of 1 variable is associated with a change in the magnitude of another variable, either in the same (positiv…
View article
ppcor: An R Package for a Fast Calculation to Semi-partial Correlation Coefficients Open
Lack of a general matrix formula hampers implementation of the semi-partial correlation, also known as part correlation, to the higher-order coefficient. This is because the higher-order semi-partial correlation calculation using a recursi…
View article
On relationships between the Pearson and the distance correlation coefficients Open
In this paper we show that for any fixed Pearson correlation coefficient strictly between −1 and 1, the distance correlation coefficient can take any value in the open unit interval (0,1).
View article
Sample Size Guideline for Correlation Analysis Open
Correlation analysis is a common statistical analysis in various fields. The aim is usually to determine to what extent two numerical variables are correlated with each other. One of the issues that are important to be considered before co…
View article
Dependent Evidence Combination Based on Shearman Coefficient and Pearson Coefficient Open
Dempster-Shafer evidence theory is efficient to deal with uncertain information. One assumption of evidence theory is that the source of information should be independent when combined by Dempster's rule for evidence combination. However, …
View article
Biostatistics series module 6: Correlation and linear regression Open
Correlation and linear regression are the most commonly used techniques for quantifying the association between two numeric variables. Correlation quantifies the strength of the linear relationship between paired variables, expressing this…
View article
Conducting correlation analysis: important limitations and pitfalls Open
The correlation coefficient is a statistical measure often used in studies to show an association between variables or to look at the agreement between two methods. In this paper, we will discuss not only the basics of the correlation coef…
View article
Estimation of the biserial correlation and its sampling variance for use in meta‐analysis Open
Meta‐analyses are often used to synthesize the findings of studies examining the correlational relationship between two continuous variables. When only dichotomous measurements are available for one of the two variables, the biserial corre…
View article
Correlation Coefficients for a Study with Repeated Measures Open
Repeated measures are increasingly collected in a study to investigate the trajectory of measures over time. One of the first research questions is to determine the correlation between two measures. The following five methods for correlati…
View article
Review of sample size determination methods for the intraclass correlation coefficient in the one-way analysis of variance model Open
Reliability of measurement instruments providing quantitative outcomes is usually assessed by an intraclass correlation coefficient. When participants are repeatedly measured by a single rater or device, or, are each rated by a different g…
View article
A Simulation Based Comparison of Correlation Coefficients with Regard to Type I Error Rate and Power Open
In this simulation study, five correlation coefficients, namely, Pearson, Spearman, Kendal Tau, Permutation-based, and Winsorized were compared in terms of Type I error rate and power under different scenarios where the underlying distribu…
View article
Inferential procedures based on the weighted Pearson correlation coefficient test statistic Open
In this note, we evaluated the type I error control of the commonly used t-test found in most statistical software packages for testing the hypothesis on vs. based on the sample weighted Pearson correlation coefficient. We found the type…
View article
A Note on the Relationship between the Pearson Product-Moment and the Spearman Rank-Based Coefficients of Correlation Open
This note derives the relationship between the Pearson product-moment coefficient of correlation and the Spearman rank-based coefficient of correlation for the bivariate normal distribution. This new derivation shows the relationship betwe…
View article
A new correlation coefficient between categorical, ordinal and interval variables with Pearson characteristics Open
A prescription is presented for a new and practical correlation coefficient, $ϕ_K$, based on several refinements to Pearson's hypothesis test of independence of two variables. The combined features of $ϕ_K$ form an advantage over existing …
View article
Sample size for estimation of the Pearson correlation coefficient in cherry tomato tests Open
The aim of this study was to determine the required sample size for estimation of the Pearson coefficient of correlation between cherry tomato variables. Two uniformity tests were set up in a protected environment in the spring/summer of 2…
View article
Some effects of non-normal distribution shape on the magnitude of the Pearson Moment Correlation Coefficient Open
All correlational statistics must be interpreted with consideration given to certain constraints. The use of the Pearson product moment correlation coefficient as a descriptive measure of relationship necessitates the assumption that the c…
View article
StaTips Part VI: Bivariate correlation Open
A very common situation in medical research, including orthodontics, is when a researcher has to verify the association between 2variables, best referred to as bivariate correlation. Bivariate correlation is an analysis that measures the s…
View article
Comparison of Pearson’s and Spearman’s correlation coefficients for selected traits of <i>Pinus sylvestris</i> L. Open
The Spearman rank correlation coefficient is a non-parametric (distribution-free) rank statistic proposed by Charles Spearman as a measure of the strength of the relationship between two variables. It is a measure of a monotonic relationsh…
View article
Confidence Intervals for the Population Correlation Coefficient Open
Computing a confidence interval for a population correlation coefficient is very important for researchers as it gives an estimated range of values which is likely to include an unknown population correlation coefficient. This paper studie…
View article
Nonparametric statistics. Part 3. Correlation coefficients Open
A measure of correlation or strength of association between random variables is the correlation coefficient. In scientific research, correlation analysis is most often carried out using various correlation coefficients without explaining w…
View article
Significance of Spearman’s Rank Correlation Coefficient Open
Significance Of Spearman’s Rank Correlation Coefficient
View article
ERRORS IN THE USE OF CORRELATION AND DETERMINATION COEFFICIENTS Open
Coefficients of correlation and determination are widely used in statistical analysis of data. Some of the errors attributed to their use are considered in this article. We confine ourselves to the case of two variables. The linear Pearson…
View article
Innovative Correlation Coefficient Measurement with Fuzzy Data Open
Correlation coefficients are commonly found with crisp data. In this paper, we use Pearson’s correlation coefficient and propose a method for evaluating correlation coefficients for fuzzy interval data. Our empirical studies involve the re…
View article
Statistical correlation coefficients for single-valued neutrosophic sets and their applications in medical diagnosis Open
The concept of single-valued neutrosophic sets (SVNSs) is considered as an attractive tool for dealing with highly ambiguous and uncertain information. The correlation coefficient of SVNSs acts as an important measure in the single-valued…
View article
Kendall correlation coefficient. Open
In the present paper, we first discuss the Kendall rank correlation coefficient. In continuous case, we define the Kendall rank correlation coefficient in terms of the concomitants of order statistics, find the expected value of the Kendal…
View article
Pearson Correlation Coefficient Open
Correlation Coefficient.NCI T hesaurus
View article
Comparison of Correlation Measures for Nominal Data Open
In social sciences, a plethora of studies utilize nominal data to establish the relationship between the variables. This, in turn, requires the correct use of correlation technique. The choice of correlation technique depends upon the unde…
View article
Comparison of Pearson’s and Spearman’s Correlation Coefficients Values for Selected Traits of <em>Pinus sylvestri</em>s L. Open
The Spearman rank correlation coefficient is a non-parametric (distribution-free) rank statistic proposed by Charles Spearman as a measure of the strength of the relationship between two variables. It is a measure of a monotonic relationsh…
View article
The Concordance Test, an Alternative to Kruskal-Wallis Based on the Kendall-$\tau$ Distance: An R Package Open
The Kendall rank correlation coefficient, based on the Kendall-$\tau$ distance, is used to measure the ordinal association between two measurements. In this paper, we introduce a new coefficient also based on the Kendall-$\tau$ distance, t…
View article
Robust Estimators for the Correlation Measure to Resist Outliers in Data Open
The objective of this research was to propose a composite correlation coefficient to estimate the rank correlation coefficient of two variables. A simulation study was conducted using 228 situations for a bivariate normal distribution to c…