Constructing A Decision Tree Using Information Gain
A decision tree can be constructed top-down using the information gain in the following way:
- begin at the root node
- determine the attribute with the highest information gain which is not already used as an ancestor node
- add a child node for each possible value of that attribute
- attach all examples to the child node where the attribute values of the examples are identical to the attribute value attached to the node
- if all examples attached to the child node can be classified uniquely add that classification to that node and mark it as leaf node
- go back to step two if there are unused attributes left, otherwise add the classification of most of the examples attached to the child node
Read more about this topic: Information Gain In Decision Trees
Famous quotes containing the words constructing, decision, tree, information and/or gain:
“The very hope of experimental philosophy, its expectation of constructing the sciences into a true philosophy of nature, is based on induction, or, if you please, the a priori presumption, that physical causation is universal; that the constitution of nature is written in its actual manifestations, and needs only to be deciphered by experimental and inductive research; that it is not a latent invisible writing, to be brought out by the magic of mental anticipation or metaphysical mediation.”
—Chauncey Wright (1830–1875)
“There are many things children accept as “grown-up things” over when they have no control and for which they have no responsibility—for instance, weddings, having babies, buying houses, and driving cars. Parents who are separating really need to help their children put divorce on that grown-up list, so that children do not see themselves as the cause of their parents’ decision to live apart.”
—Fred Rogers (20th century)
“Blessed is the man that walketh not in the counsel of the ungodly,
nor standeth in the way of sinners, nor sitteth in the seat of the
scornful.
But his delight is in the law of the Lord; and in his law doth he
meditate day and night.
And he shall be like a tree planted by the rivers of water, that
bringeth forth his fruit in his season; his leaf also shall not wither;
and whatsoever he doeth shall prosper.”
—Bible: Hebrew Psalm I (l. I, 1–3)
“So while it is true that children are exposed to more information and a greater variety of experiences than were children of the past, it does not follow that they automatically become more sophisticated. We always know much more than we understand, and with the torrent of information to which young people are exposed, the gap between knowing and understanding, between experience and learning, has become even greater than it was in the past.”
—David Elkind (20th century)
“The honest Man has, I know, that modest Desire of Gain which is peculiar to those who understand better Things than Riches; and I dare say he would be contented with much less than what is called Wealth in that Quarter of the Town which he inhabits, and will oblige all his Customers with Demands agreeable to the Moderation of his Desires.”
—Richard Steele (1672–1729)