1. 2000-10-31 Re: Direction of Bias for Omitted Variables sas-l David L. Cassell 2. 2000-10-31 Re: Direction of Bias for Omitted Variables sas-l Eyster, Sandra 3. 2000-10-31 Re: Direction of Bias for Omitted Variables sas-l shiling 4. 2000-10-30 Direction of Bias for Omitted Variables sas-l O J Nwoha