assess_transformation: Assess normality of transformed data
Description
Not all data allows for a reasonable transformation to normality using power
transformation. For example, uniformly distributed data or multi-modal data
cannot be transformed to normality. This function computes a p-value for an
empirical goodness of fit test for central normality. A distribution is
centrally normal if the central 80% of the data are approximately normally
distributed. The null-hypothesis is that the transformed distribution is
centrally normal.