997 views

### Pearson and Spearman correlations [duplicate]

I'm having a problem with choosing between Pearson and Spearman correlation. I'd like to understand clearly why I should use one or the other. I have read the questions already asked here about this ...
419 views

### Calculating concordance using either Pearson or Spearman (rank) correlations [duplicate]

I wish to calculate correlation between external rating of accounts and internal ratings of the accounts in my branch. Which out of Pearson correlation or rank correlation will be better to use and ...
206k views

### Pearson's or Spearman's correlation with non-normal data

I get this question frequently enough in my statistics consulting work, that I thought I'd post it here. I have an answer, which is posted below, but I was keen to hear what others have to say. ...
14k views

### What could cause big differences in correlation coefficient between Pearson's and Spearman's correlation for a given dataset?

The Pearson's coefficient between two variables is quite high (r=.65). But when I rank the variable values and run a Spearman's correlation, the cofficient value is much lower (r=.30). What is the ...
44k views

### Spearman's or Pearson's correlation with Likert scales where linearity and homoscedasticity may be violated

I am wanting to run correlations on a number of measurements where Likert scales were used. Looking at the scatterplots it appears the assumptions of linearity and homoscedasticity may have been ...
10k views

### What does it indicate when the Spearman correlation is a definite amount less than Pearson?

I have a bunch of related datasets. The pearson correlations between pairs of them are typically definitely larger than the spearman correlations. That suggests any correlation is linear, but one ...
17k views

### Correlation using Logistic Regression and Pearson

I am so sorry, I am beginner in statistic analysis, I have project using R to analyze the correlation between dependent variables and independents variables. In this case I have two dependent ...
27k views

### How do you estimate correlations between ordinal and binary data in SPSS?

I'm struggling with my lab report. I have a questionnaire which contains Likert responses (1-7) as well as questions that require only yes or no answers. I want to see if there is a correlation ...
2k views

### Pearson correlation between a variable and its square

Here is my R code to get familiarised with Pearson's correlation. I generate values of $X$ from 1 to 100, then find the correlation between $X$ and $X^2$: ...
1k views

### Why is a Pearson correlation of ranks valid despite normality assumption?

I am currently reading up on assumptions for Pearson correlations. An important assumption for the ensuing t-test seems to be that both variables come from normal distributions; if they don't, then ...
3k views

### Correlation of two interval scaled variables

I have two variables A and B of interval scale type. A is the birth year of a person and B is the number of years spent at university. What method would you recommend to measure the correlation?
2k views

### Normal Distribution for Pearson Correlation

I have read that the variables must be approximately normally distributed to apply Pearson correlation; However, I came across this answer here that they dont need to be, so I am confused about ...
2k views

### bootstrapping spearman vs. pearson multiple correlations

I would like to calculate simple correlations. Since my sample size is quite small and data are not normally distributed I thought about Spearman’s correlations. Then I read about bootstrapping as a ...