if (testing != null)
logger.info("Testing on " + testing.size() + " instances");
assert(numThreads.value > 0);
CRFTrainerByPR trainer = new CRFTrainerByPR(crf,constraints,numThreads.value);
trainer.addEvaluator(eval);
trainer.setPGaussianPriorVariance(var);
trainer.train(training,iterations,iterations);
return crf;
}