ontal axis of an ROC curve and measure stands for the vertical
n ROC curve,
curve=performance(my.roc,measure='tpr',
x.measure='fpr')
d on my.curve, the plot function is called to generate an ROC
o acquire the AUC, the performance function is called again,
uc must be specified for the measure parameter,
auc.obj=performance(my.roc,measure='auc')
AUC value can thus be extracted from this AUC object using the
g R code, where my.auc is the calculated AUC value and the use
y is because my.auc.obj is an S4 object,
my.auc=unlist(my.auc.obj@y.values)
neralisation
rtant issue associated with a supervised machine learning model
neralisation power. The generalisation power of a supervised
learning model is an estimation of how a constructed supervised
learning model can work well for new data. Whether a model
ell for new data is much more important than whether a model
ell for data which is used to construct the model. A process of
e generalisation power of a supervised machine learning model
he generalisation test, which has to be implemented on new data.
ning of new data is that the data has not been used for model
ion.
lassification models are supervised machine learning models,
rtainly require a generalisation test in place [Devroye, et al., 1996;
1996; Ripley, 1996]. The subject of the generalisation test of a
d machine earning model has been well-exercised for analysing
l/medical data as well. For instance, classification models have
structed for gastric and colonic epithelial tumour [Iizuka, et al.,