房地产市场与经济周期密切相关，稳定房地产对于稳定经济至关重要。由于新冠疫情，经济面临需求收缩、供给冲击等压力。房地产是国民经济的支柱产业，开发周期漫长，房价波动面临居多不确定性的影响，影响国民经济的稳定。稳定房地产市场和稳定房价波动对于稳预期、强信心、稳增长和经济高质量发展具有重大意义。

本文搜集国内外文献，厘清房价波动与房地产政策、经济波动相关性，需要考虑三个关键点，其一经济周期波动会刺激房价波动，激励国家进行房地产政策调控冲击，将导致新的房价波动。其二房地产政策调控冲击和房价波动传导过程可能会导致房价波动被低估，实物期权理论分析具有必要性。其三房地产政策、房价波动和经济波动存在复杂的关系。鉴于此，首先通过整理房地产政策，并进行整理赋值，将赋值的结果与房价波动进行对比分析。其次分析房地产开发全过程中各环节决策行为的实物期权特征。再次基于求解隐含波动率的二分法原理，设计编写基于Python语言的求解程序，测算得到房价波动率表示房价波动。最后基于测算所得的房价波动率，探析影响房价波动率的房地产政策因素和研究房价波动率与房地产政策、经济波动的相关性。

基于理论分析和实证模型分析的结果，本文得出四个结论：

（1）证实了市场统计所得的房价波动被低估了，实物期权测算得到的房价波动相较于统计所得的房价波动，能更加切实的反映现实中房价波动对经济波动的影响。

（2）房地产政策越密集，房价的波动越大。2006年到2011年之间，房地产政策使用密集，对于房价的波动影响较大，该时间段内房价的波动剧烈。

（3）政策工具选择的越平均，房价的波动越小。在2004年之前，土地政策使用较多，政策使用单一，促使房价的波动较大，在2017年之后货币政策与土地政策以及税收和综合性政策使用较为平均，房价的波动较小。

（4）经济波动引起房地产政策调控进而影响房价波动，房价波动又通过传导平抑经济波动。首先由于经济波动剧烈，为调控宏观经济，政府制定房地产政策，房地产政策出台又引起房价波动，通过房价波动平抑作用，达到政府稳定经济波动的目标。

（5）通过测算所得房价波动率识别房价波动的影响因素，发现货币超发、二手房交易税率、房企负债率和房企土地购置面积是房价波动的重要推动力。

本文提出关于稳定房价波动的建议：一方面，政府规范房地产政策发布，促进房地产政策的连续性和稳定性。着重从货币角度、税收因素、土地因素和市场因素四个方面出发稳定房价波动。另一方面，房地产开发商提升政策信息敏感度，做好市场调研，保持理性态度和现金流稳定，同时做好保交楼和物业维护服务，保障购房者信心。

The real estate market is closely related to the economic cycle, and stabilizing real estate is very important for stabilizing the economy. Due to the COVID-19 epidemic, the economy is under pressure from demand contraction and supply shock. Real estate is a pillar industry of the national economy, with a long development cycle. The fluctuation of house prices is affected by many uncertainties, which affects the stability of the national economy. Stabilizing the real estate market and stabilizing the fluctuation of house prices are of great significance for stabilizing expectations, strengthening confidence, stabilizing growth and high-quality economic development.

In this paper, we need to consider three key points to collect domestic and foreign literature and clarify the correlation between housing price fluctuation and real estate policy and economic fluctuation. First, economic cycle fluctuation will stimulate housing price fluctuation, stimulate the country to carry out the impact of real estate policy regulation, and will lead to new housing price fluctuation. Secondly, the impact of real estate policy regulation and the transmission process of house price fluctuation may lead to the underestimation of house price fluctuation, so it is necessary to analyze the real option theory. Thirdly, there is a complex relationship among real estate policy, house price fluctuation and economic fluctuation. In view of this, first of all, through sorting out the real estate policy and sorting out the assignment, the result of the assignment is compared with the fluctuation of house prices. Secondly, it analyzes the real option characteristics of decision-making behavior in all aspects of real estate development. Thirdly, based on the dichotomy principle of solving implied volatility, a solution program based on Python language is designed and written to measure the volatility of house prices to represent the fluctuation of house prices. Finally, based on the measured house price volatility, this paper analyzes the real estate policy factors that affect house price volatility and studies the correlation between house price volatility and real estate policy and economic fluctuations.

Based on the results of theoretical analysis and empirical model analysis, this paper draws four conclusions:

it is confirmed that the fluctuation of house price obtained from market statistics is underestimated. Compared with the fluctuation of house price obtained from statistics, the fluctuation of house price calculated by real options can more effectively reflect the influence of house price fluctuation on economic fluctuation in reality.

the more intensive the real estate policy, the greater the fluctuation of house prices. From 2006 to 2011, the intensive use of real estate policies had a great impact on the fluctuation of house prices, and the fluctuation of house prices was fierce during this period.

the more average the choice of policy tools, the smaller the fluctuation of house prices. Before 2004, the use of land policy was more and the use of policy was single, which made the house price fluctuate greatly. After 2017, the use of monetary policy and land policy, as well as taxation and comprehensive policy, was more even, and the house price fluctuated less.

economic fluctuations cause real estate policy regulation and control, which in turn affects house price fluctuations, which in turn stabilizes economic fluctuations through transmission. First of all, due to the drastic economic fluctuations, the government has formulated real estate policies to regulate the macro-economy, and the introduction of real estate policies has caused house price fluctuations, so as to achieve the government's goal of stabilizing economic fluctuations through the calming effect of house price fluctuations.

Identify the influencing factors of house price fluctuation by measuring the fluctuation rate of house price, and find that excessive currency, tax rate of second-hand housing transactions, debt ratio of housing enterprises and land acquisition area of housing enterprises are the important driving forces of house price fluctuation.

On the one hand, the government standardizes the release of real estate policies to promote the continuity and stability of real estate policies. Focus on stabilizing house price fluctuations from four aspects: currency, tax, land and market factors. On the other hand, real estate developers should enhance the sensitivity of policy information, do a good job in market research, maintain a rational attitude and stable cash flow, and at the same time do a good job in ensuring the delivery of buildings and property maintenance services to ensure the confidence of buyers.

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