What is the test for coercion in determining whether there is a reasonable probability of a jury agreement in a civil case?

" 'The determination whether there is a reasonable probability of [juror] agreement rests in the discretion of the trial court. [Citations.] The court must exercise its power, however, without coercion of the jury, so as to avoid displacing the jury's independent judgment "in favor of considerations of compromise and expediency." [Citation.]' [Citation.] The question of coercion is necessarily dependent on the facts and circumstances of each case. [Citation.]" (People v. Sandoval (1992) 4 Cal.4th 155, 195-196.)