All Questions
Tagged with pearson-r effect-size
12
questions
5
votes
1
answer
178
views
What references discuss the problems with phi as an association measure?
(Olivier (2013) states that
many have pointed out problems with $\phi$ as an association measure and advocate the use of odds ratios as an alternative
Unfortunately, it does not give citations for ...
- 939
1
vote
1
answer
241
views
Converting Cohen's $d$ to Pearson's $r$ $\ne$ calculated Pearson's $r$
I was calculating effect sizes for an analysis and noticed by chance that Pearson's $r$ calculated from Cohen's $d$ with a conversion formula is not the same as when I calculate the correlation given ...
- 35
1
vote
0
answers
47
views
Correlation coefficients when oversampling the extremes of a normal distribution
Running some simulations in which I generated two correlated normal variables (rho=0.3), and then took samples of this population in which the extremes of the population where oversampled (...
- 11
3
votes
2
answers
791
views
Two methods of converting Cohen's d to CL (common language effect size / Probability of Superiority) yield different results?
The common language effect size (CLES) of McGraw & Wong, 1992, also known as the probability of superiority, can be conceptualized as the probability that a person picked at random from the ...
- 743
0
votes
0
answers
20
views
Shouldn't higher r values be inversely related with effect size?
I'm conducting a Wilcoxon Rank Sum Test and read that the r from Pearson Correlation is good for determining an effect size.
Logically this does not make sense to me as the higher the effect size ...
- 81
3
votes
1
answer
10k
views
Converting between correlation and effect size (Cohen's d)
Several sources (here here here) claim that there is a relation between Cohen's d and Pearson's r if the data is paired (bivariate). This strikes me as odd since, for example, evaluating a "before and ...
- 298
0
votes
1
answer
710
views
Using transformed data in Cohen's d effect size calculations
I have used a Log10 transformation on my data to transform some non-parametric data to normally distributed so that I could run a Pearsons correlation. Field (2013) states that only problematic ...
4
votes
2
answers
495
views
Calculate effect size (e.g., Pearson r) from the output of a multiple regression
I'm looking at a multiple regression analysis in which I'm only interested in 1 of the several variables included in the model. However, the bivariate associations are not reported. I'm wondering if I ...
- 515
3
votes
1
answer
730
views
What is Pearson's r association strength?
I am trying to grasp the concept of magnitude-of-effect estimations, as opposed to standard null hypothesis testing procedures.
According to a paper by (Snyder & Lawson, 1993) the magnitude-of-...
- 207
3
votes
2
answers
3k
views
What are real strengths of association when using Pearson correlation?
I have located a table that breaks downs Pearson's correlation values into 3 categories. See below:
My question is this. One could have a large positive correlation of 1 as well as a perfect ...
- 31
9
votes
3
answers
28k
views
Reporting coefficient of determination using Spearman's rho
I have two non-normally distributed variables (positively-skewed, exhibiting ceiling effects). I would like to calculate the correlation coefficient between these two variables. Due to the non-...
- 209
1
vote
0
answers
59
views
Simple similarity comparison over time
I've seen that Pearson's r is typically used for evaluation between non-experimental conditions. However, I've also seen Pearson's r used to indicate effect size - is this acceptable?
Is it a useful ...
- 255