XEMStrategy: An EM strategy to obtain a good optimum.

In blockcluster: Co-Clustering Package for Binary, Categorical, Contingency and Continuous Data-Sets

An EM strategy to obtain a good optimum.

Description

In Co-clustering, there could be many local optimal where the algorithm may get struck resulting in sub-optimum results. Hence we applied a strategy called XEM strategy to run the EM algorithm. The various steps are defined as follows:

Details

Step-1, "xem" step:

Do several runs of: "initialization followed by short run of algorithm (few iterations/high tolerance)". This parameter is named as "nbxem" in coclusterStrategy function. Default value is 5. We call this step as xem step.

Step-2, "XEM" step:

Select the best result of step 1 and make long run of Algorithm(high iterations/low tolerance).We call this step as XEM step.

Step-3

Repeat step 1 and 2 several times and select the best result. The number of repetitions can be modified via parameter "nbtry" of coclusterStrategy function. Default value is 2.

blockcluster documentation built on June 24, 2024, 5:17 p.m.