The Firm Ecosystem Model is a dynamical model based on the empirical finding that firm characteristics, such as the tendency to innovate and competitive advantages, vary according to firm size. Firm dynamics leading to various population distributions are considered as a competition-colonization scenario in a spatially defined market, where firms of differing sizes are treated as separate species with different competition and colonization characteristics. Smaller firms, given adequate investment funds to innovate, are able to colonize available space more quickly than larger firms, and larger firms are assumed to have stronger competition characteristics and are able to outcompete smaller firms for occupied space. With startup and mortality parameters determined empirically, firm populations reach equilibria dependent on the values of the capital investment parameters. The model predictions provide a good qualitative fit to empirical data from the Business Dynamics Statistics database. Finally, we explore how alternative mortality or investment conditions affect the firm size distributions.

企业生态系统模型是基于经验发现的动态模型，该发现发现企业特征（如创新趋势和竞争优势）会根据企业规模而变化。在空间界定的市场中，导致各种人口分布的企业动态被视为竞争殖民化场景，其中规模不同的企业被视为具有不同竞争和殖民特征的独立物种。较小的公司，只要有足够的投资资金进行创新，就可以比较大的公司更快地占领可用空间，并且假定较大的公司具有更强的竞争特征，并且能够在较小的竞争中胜过较小的公司。凭经验确定启动和死亡率参数后，企业人口达到均衡取决于资本投资参数的值。模型预测对来自Business Dynamics Statistics数据库的经验数据提供了很好的定性拟合。最后，我们探索替代死亡率或投资条件如何影响企业规模分布。