Leave Some Out (LSO) is used to validate a network.  Example rows or subsets of examples are removed from the training set and used for validating.  After the optional preparation that allows Controls to be set and some row types to be excluded all but the excluded example rows are changed to training types.  One subset or a random number of example rows is then selected and changed to validating types.  The training rows are then used to train the network without the currently selected subset of validating rows.  Training continues until a stop is hit.  It is important that the controls are set with a possible stop.  The simplest stop to use with LSO is a fixed number of cycles.  Validating stops are not needed as LSO runs its own validating cycle.  When the training stops the selected subset of validating rows is used for validation.  The process is repeated until all subsets have been used once.  After the process is completed a report is produced showing the validating and training results. The report also contains the Diagnostic Array data if it available.