if (configuration.getNegative() > 0) {
            if (((InMemoryLookupTable<T>) lookupTable).getSyn1Neg() == null) {
                logger.info("Initializing syn1Neg...");
                ((InMemoryLookupTable<T>) lookupTable).setUseHS(configuration.isUseHierarchicSoftmax());
                ((InMemoryLookupTable<T>) lookupTable).setNegative(configuration.getNegative());