As discussed in the concepts of model selection and feature extraction, the two issues can be dealt with, if you have prior knowledge about:

• The appropriate feature 
• Model selection parts

Having prior knowledge of the explanatory features in the fish recognition system enabled us to differentiate amid different types of fish. We can go promote by endeavoring to envision our information and get some feeling of the information types of the distinctive fish classifications. On the basis of this  prior knowledge, apt family of models can be chosen.