在sklearn.datasets中dump_svmlight_file（）方法中的zero_based参数有什么影响？

I'm making some classification experiments using sklearn. During the experiments, I'm building csr_matrix objects to store my data and used LogisticRegression classifier on these objects and get some results. I dump the data using dump_svmlight_file and the model using joblib. But when I then load the data using load_svmlight_file and the model, I obtained (very) different results. I'm making some classification experiments usin