Hello,

I have a table of approximately 1000 pairs of values.

x is an integer between 0 and 365, representing birthday

y is an integer between 1 and 4, being a measure of achievement.

I am investigating whether there is positive correlation between x and y.

I am not sure which test to use. I have considered:

Pearson's correlation coefficient (but my variables are not bivariate normal)

Spearman's rank correlation coefficient (looks promising)

Kendall's rank correlation coefficient (but variable y has a large number of tied ranks)

I have managed to conduct a Chi-squared test for association between x and y (association was not significant), but that's not really what I want - I want to test for positive correlation.

Spearman's is tempting, so I entered the following code:

This gives rho = 0.07359, p-value = 0.009817. This seems like a significant result, but I get a Warning: "Cannot compute exact p-value with ties" so I don't know whether to trust it or not.

Is there another test that I should be using? Or can I trust this p-value and conclude that there is a significant positive correlation?

Hope you can help. Thank you - it's much appreciated.

I have a table of approximately 1000 pairs of values.

x is an integer between 0 and 365, representing birthday

y is an integer between 1 and 4, being a measure of achievement.

I am investigating whether there is positive correlation between x and y.

I am not sure which test to use. I have considered:

Pearson's correlation coefficient (but my variables are not bivariate normal)

Spearman's rank correlation coefficient (looks promising)

Kendall's rank correlation coefficient (but variable y has a large number of tied ranks)

I have managed to conduct a Chi-squared test for association between x and y (association was not significant), but that's not really what I want - I want to test for positive correlation.

Spearman's is tempting, so I entered the following code:

Code:

`cor.test(x, y, alternative = "greater", method = "spearman")`

Is there another test that I should be using? Or can I trust this p-value and conclude that there is a significant positive correlation?

Hope you can help. Thank you - it's much appreciated.

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