In the single factor case, given that R i = E(R i ) + i F

In the single factor case, given that R_i = E(R_i ) + β_i F + ϵ_i , the APT model specified as E(R_i ) = γ⁰ + γ_iβ is called the exact APT model by Huberman and Wang (2017). Huberman (1982) considers the representation E(R_i ) = γ⁰+

γ₁β_i + α_i , which Huberman and Wang refer to as an approximate APT model.

Here it is assumed that ∑ⁿ_i=1 α_i = 0 and∑ⁿ_i=1 α_iβ_i = 0. How can αis be interpreted in economic terms?