Re: Gamma Correlation pro's & con's



John Uebersax schrieb:

I don't know if this applies to your situation, but if variables are
ordered-category (i.e., just a few levels), rather than ordinal
(ranks), then:  (1) both the gamma statistic and Spearman's rho are
affected by the large number of tied cases that result; and (2) the
polychoric correlation coefficient avoids this.
--
John Uebersax PhD

In our data we have got lot's of ties. The data is ordinal, either left screwed or right screwed.
We defined the values to be 0,1,2 and 3. Until now the data has been analysed with Spearman Rank Correlation, but because of all the ties we are looking for a test which fits better.

Konstanze

.

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