def plurality_value(examples):
"""
Return the most popular target value for this set of examples.
(If target is binary, this is the majority; otherwise plurality).
"""
popular = argmax_random_tie(values[target], key=lambda v: count(target, v, examples))
return DecisionLeaf(popular)
def choose_attribute(attrs, examples):
"""Choose the attribute with the highest information gain."""
return argmax_random_tie(attrs,
key=lambda a: information_gain(a, examples))