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Prediction of residuary resistance of sailing yachts at the initial design stage is of a great value for evaluating the ships performance and for estimating the required propulsive power

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Prediction of residuary resistance of sailing yachts
at the initial design stage is of a great value for evaluating the ships performance and for
estimating the required propulsive power. Essential inputs include the basic hull dimensions
and the boat velocity. The Delft data set comprises 308 full-scale experiments, which were
performed at the Delft Ship Hydromechanics Laboratory for that purpose. The results of
these experiments are in the file yacht.dat. These experiments include 22 different hull forms,
derived from a parent form closely related to the Standfast designed by Frans Maas.
The columns correspond to the following variables (in order):
• Residuary resistance per unit weight of displacement, adimensional;
• Longitudinal position of the center of buoyancy, adimensional;
• Prismatic coefficient, adimensional;
• Length-displacement ratio, adimensional;
• Beam-draught ratio, adimensional;
• Length-beam ratio, adimensional;
• Froude number, adimensional.
Using this data:
1. Fit a model to predict the resistance per unit weight of displacement as a function of
the other variables. Discuss if this is a valid model.
2. Given the above model as a starting point, investigate how it can be improved. In this
you should consider:
(a) The use of training and validation datasets. The data should be divided such that
the split between these two sets is approximately 80% for training and 20% for
validation.
(b) Are all variables important for the model?