Reporting the best test accuracy in a research paper? I am running a random forest classifier for binary classification. I have split the dataset into training and testing. From training data, I select 70% of the data for hyperparameter tuning, I used 5 fold cross validation for that. Then I use the hyperparameters that produce high mean cross-validation accuracy (let's call it validation accuracy) and train the model on full training data and check the model on testing data. I get the testing accuracy.
My question is-
i) Should I report the best validation accuracy or the best testing accuracy?
I can use the seed (by proving random_state = xyz in random forest classifier) to fix the samples used for bootstrapping, which gives the best test accuracy.
If I need to report both the accuracies, can I select the seeds that give good validation accuracy and a good testing accuracy? What if I use the best test accuracy I got and report that in the paper?

Typically the test accuracy is reported unless you're performing a particular analysis on your validation routine.
Choosing the best seed for your data is cheating. To stabilize your results, it's better to increase your number of bootstrap iterations so that you get similar results even if you change seeds. The seed should be there only for the purpose of reproducibility.
