Online feedback mechanisms have become an important tool for consumers to gauge the relative risk of dealing with people they may never meet in person. But relying on these online mechanisms may leave us misinformed, as customers only see what people are willing to report. Chrysanthos Dellarocas , an associate professor of information systems at the Smith School, allows users of bidirectional feedback mechanisms to see a more reliable picture of what is happening in private transactions by taking into account the response that never gets posted -- silence.