In a certain place, two production management methods A and B were tried out in two factories. Their pilot work was carried out as follows: Method A was tried out in a large factory with leadership of high education level; Method B was tried out in a small factory with leadership of low education level, and Method A resulted in good economic benefits; Method B not good. 
The conditions of the two factories are different and cannot be used as experimental bases to test the two management methods
 it was concluded that Method A was the reason for achieving better economic benefits.