What increases your chances of being audited? Having a home office? Small business?
what decreases your chances? Does hiring an accountant do your taxes makes it look more credible to IRS agents?
Here is an article that claims to know something about it. Here are a selection of quotes:
The IRS says there are several ways a return can be selected for audit and the first is via the agency's computer-scoring system known as Discriminant Information Function, or DIF. The IRS evaluates tax returns based on IRS formulas, and DIF is based on deductions, credits and exemptions with norms for taxpayers in each of the income brackets. The actual scoring formula to determine which tax returns are most likely to be in error is a closely guarded secret. But Nath, a tax attorney in the Washington, D.C., area, says it's no mystery the system is designed to screen for returns that could put more money in the government Treasury.
So what is likely to trigger a discriminant information function red flag?
Here's a few things: