From the course: Machine Learning and AI Foundations: Decision Trees with SPSS

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How CHAID handles continuous variables

How CHAID handles continuous variables

From the course: Machine Learning and AI Foundations: Decision Trees with SPSS

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How CHAID handles continuous variables

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- [Instructor] Our continuous variable will be age. CHAID actually starts by converting age into deciles. It has to do this because chi square can't be run on continuous variables, yet in this case we get only two notes. So what's going on? It seems like age, 13, is an important cut off, It seems like age, 13, is an important cut off, which certainly is consistent with this notion of women and children first. So how does CHAID do it? When we force it into more segments, we get a better sense of what the deciles must have looked like. In fact if we take a closer look at the sample size we can see that node 14 has 41 records we can see that node 14 has 41 records out of a total in this particular tree of 500. So about the size we would expect a decile to be. By the way deciles aren't going to be exactly 50 because we're talking about integers here and for that reason you're not going to get that exact number. If we move on to node 15, we see that that has 48. Also about what we expect…

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