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)
“The great pines stand at a considerable distance from each other. Each tree grows alone, murmurs alone, thinks alone. They do not intrude upon each other. The Navajos are not much in the habit of giving or of asking help. Their language is not a communicative one, and they never attempt an interchange of personality in speech. Over their forests there is the same inexorable reserve. Each tree has its exalted power to bear.”
—Willa Cather (1873–1947)
“Rejecting all organs of information ... but my senses, I rid myself of the Pyrrhonisms with which an indulgence in speculations hyperphysical and antiphysical so uselessly occupy and disquiet the mind.”
—Thomas Jefferson (1743–1826)
“I had been in the hurrying waters too long not to appreciate an opportunity to lie on the bank and rest, watch others, and gain strength for the coming years.”
—Ellen Henrietta Swallow Richards (1842–1911)