# How to calculate the correlation R?

### How to calculate the correlation R?

the coefficient of r-correlation is a unitless value between -1 and 1. Statistical significance is indicated by a p-value. Therefore, correlations are usually expressed using two key numbers: r = and p = . More r is close to zero, the weaker the linear relationship.

### How to do a correlation on r studio?

Several methods are available in R to draw a correlogram. You can use either symnum() function, corrplot() function or scatter plots to To do the graph of the matrix of correlation.

### How to calculate the result of a t test?

The result is a data frame, which can be easily added to a graph using the R package ggpubr. t.test() [paquet stats] : basic R function to perform a t-test. Calculate and report the effect size of the t-test using Cohen’s d.

### What is Normality Test in Analysis of Variance?

Testing for Normality in R. Many of the statistical methods, including correlation tests, regression tests, t-tests, and analysis of variance, assume that the data follows a normal distribution or a Gaussian distribution. These tests are called parametric tests because their validity depends on the distribution of the data.

### How to calculate the missing value type of a CSV file?

It is therefore necessary to specify to R the type of missing value that it will encounter in the file. This is done by adding the option na.string=”Missing_encoding” in the read line. So if your .csv was obtained from Excel or Open office, the read instruction is read.csv2(“file_name.csv”, na.string=””)

### How to calculate the effect of a t test?

Calculate and report the effect size of the t-test using Cohen’s d. The “d” statistic redefines the difference of means as the number of standard deviations between these means. Conventional t-test effect sizes, proposed by Cohen, are: 0.2 (small effect), 0.5 (moderate effect), and 0.8 (large effect) (Cohen 1998).