Threefold vs. fivefold cross validation in one-hidden-layer and two-hidden-layer predictive neural network modeling of machining surface roughness data

Predictability of a manufacturing process or system is vital in virtual manufacturing. Various data mining techniques are available in developing predictive models. Cross validation is critical in determining the quality of a predictive model and the costs in data collection and data mining. Several cross-validation (CV) techniques are available, including the v-fold CV, leave-one-out CV, and the bootstrap type of CV. Some past studies have not revealed any statistical advantages of using tenfold cross validation over fivefold cross validation. Determining the number of hidden layers is important in predictive modeling with neural networks. This study attempts to compare the performance of fivefold over threefold CV and that of one-hidden-layer over two-hidden-layer neural nets in predictive modeling for surface roughness parameters defined in ISO 13565 for turning and honing. Statistical hypothesis tests and different prediction errors are employed to compare the competitive models. This study does not reveal any significant statistical advantages of using fivefold CV over threefold CV and of using two-hidden-layer neural nets over one-hidden-layer neural nets for the cases under study. Furthermore, the procedure presented here is applicable in comparing competitive data modeling or data mining methods.