PCA analysis and log transformation of data
Posted: Tue May 11, 2021 10:45 am
I have a couple of questions regarding the cleaning of data before importing into Jamovi for PCA,
My data is multi-variate, compositional geochemical data. Missing values, censored data and units have already been cleaned (all in ppm). Some measurements are very small, but still important to discern. Some of my variable are not normally distributed.
Do I need to log-transform my data before I carry out PCA in Jamovi?
If I do need to transform it, I spotted the 'readthedocs' article which refers to LOG10 transform, but I am very confused as to how I add the correct transform formula into Jamovi (the examples seem to focus on categories, not log ratio transformations or don't quite go far enough in terms of showing an example for this).
Any help would be very much appreciated.
My data is multi-variate, compositional geochemical data. Missing values, censored data and units have already been cleaned (all in ppm). Some measurements are very small, but still important to discern. Some of my variable are not normally distributed.
Do I need to log-transform my data before I carry out PCA in Jamovi?
If I do need to transform it, I spotted the 'readthedocs' article which refers to LOG10 transform, but I am very confused as to how I add the correct transform formula into Jamovi (the examples seem to focus on categories, not log ratio transformations or don't quite go far enough in terms of showing an example for this).
Any help would be very much appreciated.