Abstract: By introducing the belief differences of group members,combining the real option theory and asset pricing theory,we give an enterprise group investment model under the optimal capital structure,and analyze the effects of debt interest,cash flow volatility,reversibility and polarization on the investment threshold.The results show that the group abandonment decision is dominated by the belief median,while the key members of investment decision will shift with polarization.The volatility and polarization of cash flow are positively correlated with the investment threshold,while reversibility and debt interest are negatively correlated with the investment threshold.Under low cash flow volatility,polarization can offset the influence of reversibility on the group investment threshold,and under low reversibility,the changes of debt interest and polarization do not change the key members' status in group investment decision-making.

Key words: group decision-making, real options, capital structure