Projection Theory Property The projection Ily minimizes‖y-21|y,Vz∈Z. Why? ly-(Ily +u)y=((y-Ily)-v,(y-Ily)-vy anyz∈z Iy-IIyly-2(y-IIy, uy +la, VUEZ 0:v∈z SMA-HPO⊙1999M Poisson in IR: Theory Practice 6