What is the standard of evidence used to prove identity in criminal cases?

Evidence admissible to prove intent must only support the inference that the defendant probably possessed the same intent in each instance. (People v. Ewoldt, supra, 7 Cal.4th at p. 402.) However, evidence relevant to prove identity requires the greatest degree of similarity between the charged and uncharged offense such that "'[t]he pattern and characteristics of the crimes must be so unusual and distinctive as to be like a signature.' [Citation.]" (People v. Ewoldt, supra, 7 Cal.4th at p. 403.)