Furthermore, the conditions for the preactivation (co)polymerization of ethylene or a mixture of ethylene and another olefin are not particularly limited, as long as 0.01 g to 5,000 g, preferably 0.05 to 2,000 g, more preferably 0.1 to 1,000 g, of polyethylene (A) is formed per gram of the transition metal compound catalyst component.