predict 8 outputs one by one to get better results

Today, I predicted 8 outputs one by one to get a better result than predicting them together.

Summary:

The following two methods are inspired from honoring relationship between 4 cond and 4 perm.

First, I build two models. The first is to use log data to predict  4 cond. The second is to use 4 cond to predict 4 perm.
The prediction accuracy of 4 cond is good, 4 R2 of testing data are 0.80, 0.90, 0.86, 0.86.
But using 4 predicted cond to predict 4 perm is not good. 4 R2 of testing data are 0.54, 0.65, 0.56, 0.47.

Second, I build eight models.
I predict 8 outputs together first for ten times and average the R2 results. The accuracy from top to bottom is cond 2 1 3 4 and perm 2 1 4 3.
ANN1: log data   to   cond 2;
ANN2: log data + cond 2   to   cond 1;
ANN3: log data + cond 2 1   to   cond 3;
ANN4: log data + cond 2 1 3   to   cond 4;
ANN5: log data + cond 2 1 3 4   to   perm 2;
ANN6: log data + cond 2 1 3 4 + perm 2  to   perm 1;
ANN7: log data + cond 2 1 3 4 + perm 2 1   to   perm 4;
ANN8: log data + cond 2 1 3 4 + perm 2 1 4   to   perm 3.

The result improved. 8 R2 of testing data in the above order are 0.89, 0.91, 0.88, 0.87, 0.71, 0.64, 0.64, 0.65.

Tomorow, I will see if I can improve prediction accuracy by other methods.