异质性预期、投资者行为与房价波动：上海和广州的双城记?

房地产市场中存在大量的投资者，其市场行为会使房价出现大幅的波动，从而引起市场不稳定。文章在引入投资者异质性预期假设的基础上，构建了包含房地产消费者、投资者、供给者在内的房地产市场均衡模型，分析了房地产市场中基本面型投资者和趋势型投资者的异质性行为对房价变动的影响，并利用上海和广州两个一线城市的实际数据进行了对比分析。研究结果表明：在房地产市场中，两类投资者对于未来房价不同的预期以及投资行为会引起房价的变动；上海投资者的行为整体上会使上海的房价始终处于不断上涨的趋势中，而广州投资者的行为会随着投资策略的转变而使静态下的“整体上推动房价趋势型变化”转变为“整体上将房价‘拉回’基本面价格”；房地产市场中的投资者占比会显著影响房价的变动趋势，当基本面型投资者占比上升时，房价偏离度和房价变动率降低，而当这类投资者占比达到峰值时，房价会出现拐点；投资者之间的策略转换速度也会通过引起基本面型投资者占比的变化，引起房价的频繁波动，而且策略转换速度越快，房价波动越频繁。

Heterogeneous Expectation,Investor Behavior and Fluctuations in Housing Prices:Tale of Two Cities between Shanghai and Guangzhou

In real estate market,there are a lot of investors,and their market behavior leads to fluctuations in housing prices to a big margin,thus resulting in market instability. Based on the introduction of investors’heterogeneous expectation assumptions,this paper builds up the equilibrium model of real estate market including real estate consumers,in-vestors and suppliers.It analyzes the impact of heterogeneous behavior of fundamental-based and trend-based investors on fluctuations in housing prices and makes a comparative study by using the real data of Shanghai and Guangzhou as two first-tier cities.It comes to the results as follows:firstly,in real estate market,different expectation of future housing prices by these two categories of investors and investment behavior can result in changes in housing prices;secondly,Shanghai investor behavior overall leads to constantly rising trend in Shanghai housing prices all the time,and Guangzhou investor behavior results in the transformation from overall pushing trend-based changes in housing prices under origi-nal static condition to overall pulling housing prices back to the fundamental prices with changes in investment strategy;thirdly,investor proportion in real estate market signifi-cantly affects change trend of housing prices;when the proportion of fundamental-based investors rises,the deviation and change rate of housing prices reduce,and when the pro-portion of fundamental-based investors reaches the peak,housing prices are at an inflection point;fourthly,the strategy change speed among investors also gives rise to changes in the proportion of fundamental-based investors and thereby frequent fluctuations in housing prices,and quicker strategy change speed leads to more frequent fluctuations in housing prices.