The researchers said the new study speaks to the question of whether celebrity sponsorship has an impact on a firm's bottom line, McClatchy-Tribune News Service reports.
"Our analysis makes clear that while having a celebrity of Tiger Woods' stature as an endorser has undeniable upside, the downside risk is substantial, too," said Victor Stango, professor of economics.
Stango and fellow economics professor Christopher Knittel studied the stock market for 13 days after Woods crashed his car outside his Florida home Nov. 27. Since then, several women have said they had romantic affairs with Woods.
Woods eventually confessed to infidelity and lost major sponsorships.
The UCD economists compared returns for Woods' sponsors to those of the total stock market and of each sponsor's closet competitor, a UC Davis news release states.
Shareholder value fell 2.3 percent - or about $12 billion. The pattern of losses is unlikely to stem from ordinary variation of stock prices, the researchers stated in their study.
Investors in three sports-related companies - Tiger Woods PGA Tour Golf, Gatorade and Nike - fared the worst, experiencing a 4.3 percent loss, or about $6 billion.