Decision tree always outputs the same result

[vallettea]

Considering your machine_learning/examples/DecisionTree.js, whatever the input, teh output is always the same:

> console.log("Classify : ", dt.classify(['(direct)','USA','yes',5]));
Classify :  { None: 6, Basic: 5 }
undefined
> console.log("Classify : ", dt.classify(['slashdot','USA','yes',18]));
Classify :  { None: 6, Basic: 5 }
undefined
> console.log("Classify : ", dt.classify(['kiwitobes','France','yes',23]));
Classify :  { None: 6, Basic: 5 }
undefined
>
> console.log("Classify : ", dt.classify(['(direct)','USA','yes',5]));
Classify :  { None: 6, Basic: 5 }
undefined
> console.log("Classify : ", dt.classify(['(direct)','USA','yes',500]));
Classify :  { None: 6, Basic: 5 }