In a mean-variance framework with a representative agent, any linear model for the cross section of expected returns can be supported as an equilibrium as long as the market portfolio is spanned by the factor mimicking portfolios. Any set of factors is admissible as long as the spanning condition is satisfied. Factors based on size, book-to-market, momentum, investment, profitability, behavioral biases, principal components, or any combination of these can be used as equilibrium factors. An equilibrium model with M risk factors can be reduced to a collection of M models where each model has a single risk factor, which is covariance with the market portfolio.

在具有代表代理的均值方差框架中，只要市场投资组合被模仿投资组合的因素所覆盖，则可以为预期收益横截面的任何线性模型提供支持，以达到均衡。只要满足扩展条件，任何一组因素都是允许的。基于规模，账面价值，动量，投资，盈利能力，行为偏见，主要成分或这些因素的任意组合的因素都可以用作平衡因素。可以将具有M个风险因素的均衡模型简化为M个模型的集合，其中每个模型都具有一个风险因子，该风险因子与市场投资组合具有协方差。