Not sure why it was removed, but the documentation states: "SAS Enterprise Miner 5.3 supports conversion of SAS Enterprise Miner 4.3 projects whose process flow diagrams contain the Link Analysis node. Link Analysis nodes from SAS Enterprise Miner 4.3 process flow diagrams appear and function in diagrams that were converted for use with SAS Enterprise Miner 5.3, but the Link Analysis node cannot be added to a new SAS Enterprise Miner 5.3 diagram. If you want to analyze transaction data, refer to the SAS Enterprise Miner 5.3 Association, Path Analysis, and Market Basket nodes. If you want to analyze training data, continue to use the Link Analysis node from SAS Enterprise Miner 4.3."
see: http://support.sas.com/documentation/whatsnew/91x/emgui53whatsnew.htm
