Notes
1 The concept of alpha is model-specific, and we shall give particular definitions for particular models. Generally it refers to expected excess return relative to some equilibrium pricing theory.
2 Stivers (Citation2003) derives a similar result. In expectation, both and
are equal to zero. We use realised values of the cross-sectional variation in alpha and the cross-sectional correlation between alpha and beta, which may in effect differ from zero.
3 We are reminded by a referee that this strategy would probably be difficult to implement in practice.