新一轮猪肉储备政策评估——基于理性预期库存模型

摘要

China has clarified the response mechanism of using buffer reserve to stabilize hog market since 2009. The regulation rules have been updated twice. However, whether these adjustments can achieve better policy outcome is uncertain. This paper adopted and calibrated the rational expectation storage model using parameters representing hog market and government reserve interventions in China to simulate hog price movement and policy costs in the long run under two different policy scenarios: 2012 edition and 2015 edition, respectively. This paper also discussed the impacts of adjusting reserve capacity and changing triggering conditions for reserve intervention and forecasted the changes in policy outcomes and costs when supply and demand elasticities decreased. Results show that the coefficient of variation of hog price will decrease under the policy intervention scenarios. Comparing 2012 edition policy and 2015 edition policy, results show that under 2015 policy, hog market performs better with lower costs (by 9.98 billion yuan), despite slightly decreased efficiency and the probability of hog prices below the lower limit is significantly reduced. The impact of adjusting reserve capacity is limited and reducing storage costs can significantly reduce policy costs. The efficiency of reserve to stabilize price volatility is weakening when demand elasticity is lower and policy costs may increase. In summary, this paper provides some suggestions: reducing government intervention, encouraging the participation of private sectors, and improving hog and pork market monitoring and early warning system.%自2009年明确储备干预生猪市场的响应机制以来,储备调控政策经历两次调整,但是,这样的调整能否更好地实现政策目标未有定论.根据中国生猪生产和消费市场的特征及储备调控的具体实践对理性预期库存模型进行校准,模拟了2012年版和2015年版政策下生猪价格波动的长期趋势和政策成本,探讨了调整储备规模和改变储备触发条件对政策绩效和成本的影响,评估了储备干预政策在供需弹性双降背景下的绩效和成本变化.结果表明,当存在储备调控政策时,生猪价格的变异系数会下降.与2012年版相比,执行2015年版政策时,生猪价格低于下限的概率显著降低,有利于发挥市场的功能,同时,政策成本节约99.80亿元.但是,平抑生猪价格波动的能力略低于2012年版政策.调整储备规模对政策绩效和成本的影响都有限,降低储存成本能显著降低政策成本.当需求弹性下降时,储备干预平抑价格波动的能力会减弱,还有可能增加政策成本.因此,提出储备政策调整的方向是减少政府干预,稳定生猪市场需要发挥私人储备的作用,政府应该进一步完善生猪及猪肉市场的监测预警体系.