v1.4.0

This release contains breaking changes from v1.3.x, mainly in how wrapper functions iht() and cross_validation() are called. The main purpose of this release is to set up our code for our next publication. The next release, v1.4.1, will likely be the finalized code for our 2nd paper.

In summary, we added the following in the v1.4 release:

• Better wrapper functions: now there are only 1 iht() and 1 cross_validate() routine to call, instead of 3. This should improve user experiences.
• Dramatically improve cross-validation efficiency: no more SnpArray copying!
• Dramatically improve efficiency for multivariate analysis
• Add proportion of variance explained (PVE) estimation
• CI testing in Julia 1.6