Stock index futures rose on Friday in thin volume as key euro zone bond yields eased ahead of the release of U.S. inflation data.

Reflecting improved investor confidence, benchmark Italian bond yields stabilized below 7 percent and Spanish yields also fell. Still, worries persisted over possible sovereign credit downgrades to the euro zone members.

European shares were slightly higher early Friday as mining stocks rose, tracking metals. Copper prices added nearly 2.3 percent. <.EU>

Barry Ritholtz, chief market strategist at Fusion IQ in New York, said the rise in futures is in line with end-of-year positioning and a quiet morning in Europe.

When you wake up and there isn't any bad news out of Europe, he said, there's a general sense of being more comfortable with risk.

S&P 500 futures rose 9.3 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures rose 62 points, and Nasdaq 100 futures added 16.25 points.

Online gamesmaker Zynga Inc is expected to make a strong debut on the Nasdaq Friday after it priced its initial public offering at $10 per share, the top end of its range.

The Labor Department will release the November Consumer Price Index at 8:30 a.m. EST. Economists expect a 0.1 percent rise, compared with a 0.1 percent drop in October.

We've been hearing about this hyperinflation coming and some how it's been like 'Waiting for Godot,' Ritholtz said. It's hard to get terribly worried about inflation.

Research In Motion Ltd posted a sharp drop in profit on Thursday, offered a dismal outlook for BlackBerry shipments during the holidays and delayed the likely arrival of a make-or-break overhaul of its smartphones. The stock dropped nearly 10 percent to $13.64 in premarket trading.

(Reporting by Rodrigo Campos; editing by Jeffrey Benkoe)