What is the test for admitting evidence of an uncharged crime?

"Evidence of uncharged offenses 'is so prejudicial that its admission requires extremely careful analysis. [Citations.]' [Citations.] 'Since "substantial prejudicial effect [is] inherent in [such] evidence," uncharged offenses are admissible only if they have substantial probative value.' [Citation.]" (People v. Ewoldt (1994) 7 Cal.4th 380, 404.) "'"[H]ow much 'probative value' proffered evidence has depends upon the extent to which it tends to prove an issue by logic and reasonable inference (degree of relevancy), the importance of the issue to the case (degree of materiality), and the necessity of proving the issue by means of this particular piece of evidence (degree of necessity)." [Citation.]' [Citation.] '[B]ecause a motive is ordinarily the incentive for criminal behavior, its probative value generally exceeds its prejudicial effect, and wide latitude is permitted in admitting evidence of its existence [citations].' [Citation.]" (People v. Pertsoni (1985) 172 Cal.App.3d 369, 375.)