A
confusion matrix is an effective visualization technique to diagnose how a classification algorithm is behaving. You can create one easily in
Mathematica given a list of 2-tuples, where the 2-tuple is of the form {ground truth category, predicted category}.
ConfusionMatrix[gndpre_List] :=
With[
{categories = Union[Flatten[gndpre]]},
Partition[
Flatten[
Table[
Count[gndpre, {row, col}],
{row, categories},
{col, categories}
]
],
Length[categories]
]
]