In Econometric Theory, volume 17, number
1, an excellent solution to problem 00.1.3 also had been
submitted by S. Puntanen, G.P.H. Styan, and H.J. Werner,
and this fact was inadvertently omitted. In the same issue,
in the restatement of problem 00.1.1, the phrase “skew
symmetric” should read “real skew symmetric”;
this modification was suggested by S. Puntanen, G.P.H.
Styan, and H.J. Werner.
A corrigendum to Problem 01.2.2 is also described.