# Any packages for polychoric correlation?

**URL:** <https://discourse.julialang.org/t/any-packages-for-polychoric-correlation/36515>\
**Category:** Statistics\
**Created:** [March 25, 2020, 7:53pm UTC](https://discourse.julialang.org/t/any-packages-for-polychoric-correlation/36515 "2020-03-25T19:53:43Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![brett\_knoss](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/brett_knoss/32/13050_2.png) [@brett\_knoss](https://discourse.julialang.org/u/brett_knoss)\
**Post date:** [March 25, 2020, 7:53pm UTC](https://discourse.julialang.org/t/any-packages-for-polychoric-correlation/36515/1 "2020-03-25T19:53:43Z")

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I’m analyzing a survey that has a lot of ratings scales. Is there a package to do polychoric correlations?

If not would anyone be willing to take a crack at creating such a thing?

> **[A Generalized Definition of the Polychoric Correlation Coefficient](https://escholarship.org/uc/item/583610fv)**
>
> Author(s): Ekström, Joakim | Abstract: The polychoric correlation coefficient is a measure of association for ordinal variables which rests upon an assumption of an underlying joint continuous distribution. More specifically, in Karl Pearson’s...

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**Author:** ![takuizum](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/takuizum/32/12040_2.png) [@takuizum](https://discourse.julialang.org/u/takuizum)\
**Post date:** [July 28, 2021, 8:05am UTC](https://discourse.julialang.org/t/any-packages-for-polychoric-correlation/36515/2 "2021-07-28T08:05:02Z")

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Hi, I’m developing a new package, [ParallelAnalysis](https://github.com/takuizum/ParallelAnalysis.jl).

In this package, I implemented a function to compute polychoric correlation based on the normal distribution and the 2 step MLE estimation procedure, suggested by [Olsson](https://link.springer.com/article/10.1007/BF02296207).

Let’s try using `polycor` function.

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**Author:** ![brett\_knoss](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/brett_knoss/32/13050_2.png) [@brett\_knoss](https://discourse.julialang.org/u/brett_knoss)\
**Post date:** [August 6, 2021, 2:49am UTC](https://discourse.julialang.org/t/any-packages-for-polychoric-correlation/36515/3 "2021-08-06T02:49:21Z")

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Thanks, I’m interested in this.