What is the test for determining the fair value of a corporation's shares?

Corporations Code section 2000, subdivision (c), provides that the court shall appoint three disinterested appraisers to appraise the fair value of the shares, and that the [168 Cal.App.3d 301] determination of fair value by the appraisers, or a majority of them, when confirmed by the court, "shall be final and conclusive upon all parties." Where, however, the determination of the fair value of the shares by the appraisers, or a majority of them, is erroneous, it is "the duty of the trial court to examine the matter de novo and to fix a proper value...." (Venables v. Credential Ins. Agency, Inc. (1956) 140 Cal.App.2d 724, 727, 295 P.2d 547.)