ULS logs are blank

SharePoint Server 2010 on Windows Server 2008 R2 64-bit, using least privilege security model.

Problem: ULS logs (servername-date.log) are blank, 0 kb.

Service accounts used to run Web Analytics, Timer, and Tracing services have full control access to all files in the C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\LOGS folder, and services were then restarted.

Logging is set to verbose for all.