One Midwest grocery chain used the data mining tool to analyze local buying patterns. They discovered that when men bought diapers on Thursdays and Saturdays, they also tended to buy beer. Further analysis showed that these shoppers typically did their weekly grocery shopping on Saturdays. On Thursdays, however, they only bought a few items. The retailer concluded that they purchased the beer to have it available for the upcoming weekend. The grocery chain could use this newly discovered information in various ways to increase revenue. For example, they could move the beer display closer to the diaper display. And, they could make sure beer and diapers were sold at full price on Thursdays. WalMart captures point-of-sale transactions from over 2,900 stores in 6 countries and continuously transmits this data to its massive Teradata data warehouse. WalMart allows more than 3,500 suppliers, to access data on their products These suppliers use this data to identify customer buying patterns at the store display level . They use this information to manage local store inventory and identify new merchandising opportunities. to build a model of customer behavior that could be used to predict which customers would be likely to respond to the new product. By using this information a marketing manager can select only the customers who are most likely to respond. The (NBA) is exploring a data mining application that can be used in conjunction with image recordings of basketball games. The Advanced Scout software analyzes the movements of players to help coaches orchestrate plays and strategies. For example, an analysis of the play-by-play sheet of the game played can reveal that when player A played the Guard position, the opposite teams player B attempted four jump shots and made each one! Advanced Scout not only finds this pattern, but explains that it is interesting because it differs considerably from the average shooting percentage of 49.30% for the team during that game.
DT algorithm has been successfully applied to a wide range of learning tasks from medical diagnosis to classifying equipment malfunction by their cause Simple to understand Works with data types
Decision trees classify instances by sorting them down the tree from the root to some leaf node, which provides the classification of the instance. Each node in the tree specifies a test of some attribute of the instance, and each branch descending from that node corresponds to one of the possible values for this attribute Example: This tree classifies Saturday mornings according to whether or not they are suitable for playing tennis This family of algorithms infers decision trees by growing them from the root downward, greedily selecting the next best attribute for each new decision branch added to the tree. During the dop-down construction of the tree a decision to which attribute to put as a root or later to split on, needs to be made. In order to determine which attribute is the best classifier of the input instances, the algorithm uses statistical test called information gain. (Information gain of an attribute can be defined by measuring the expected reduction in entropy caused by partitioning the examples according to that attribute. ) How well a given attribute separates the training examples according to their target classification.
Decision trees classify instances by sorting them down the tree from the root to some leaf node, which provides the classification of the instance. Each node in the tree specifies a test of some attribute of the instance, and each branch descending from that node corresponds to one of the possible values for this attribute Example: This tree classifies Saturday mornings according to whether or not they are suitable for playing tennis This family of algorithms infers decision trees by growing them from the root downward, greedily selecting the next best attribute for each new decision branch added to the tree. During the dop-down construction of the tree a decision to which attribute to put as a root or later to split on, needs to be made. In order to determine which attribute is the best classifier of the input instances, the algorithm uses statistical test called information gain. (Information gain of an attribute can be defined by measuring the expected reduction in entropy caused by partitioning the examples according to that attribute. ) How well a given attribute separates the training examples according to their target classification.