When I go home from the office, I face a traffic jam, as shown in the following image, as many other commuters in Bangalore do almost every day.

I thought if I could only predict a traffic jam, I would reach home early to play with my son. I observed that if it rains and if it is a weekday and if it is past 4:30 PM in the dial, a traffic jam is highly likely.

So I thought I could use a decision tree to predict whether there will be a traffic jam today or not. In the following example, I used a toy dataset that I fabricated. In the real settings, the data has to be filled following a month or few months' observations, because anomalies do exist. Sometimes, even if it rains and even if it is a weekday, there is no traffic jam. The reason may be that there is a cricket match that people want to watch and they have taken a day off work or are working from home. However, these sorts of situations are not common and shouldn't be considered...