(Updates to early afternoon U.S. trading, adds volatility index)
* Wall St indexes experiencing big swings
* Nikkei ends down 4.7 pct
* Oil and industrial metals fall
NEW YORK, Feb 6 (Reuters) - U.S. stocks were down moderately in early afternoon trading on Tuesday but were swinging wildly between positive and negative territory, a day after the Dow and S&P 500 indexes saw their biggest one-day declines in more than six years, while a world stock index dropped more than 1 percent.
European shares closed down more than 2 percent, and losses for MSCI's widely tracked 47-country world index broke $4 trillion, with shares in emerging markets also down sharply.
"We're bouncing around here. The market clearly hasn't decided what the sentiment for the day is," said Janna Sampson, co-chief investment officer at Oakbrook Investments LLC in Lisle, Illinois.
The swings between positive and negative on Wall Street indexes were wide, with a more than 930-point difference between the Dow's intraday high and low. Markets were volatile for a second day as well after many months of mostly calm trading.
The Cboe Volatility Index, known as the VIX and the most widely followed barometer of expected near-term volatility for the S&P 500, also hovered between positive and negative territory, a day after it hit its highest level since 2015. The move left market participants grappling with the implosion of products that bet against volatility.
The blue-chip Dow Jones Industrials index, which on Monday slumped briefly by more than 10 percent from its Jan. 26 record high.
Economically sensitive S&P materials, technology and consumer discretionary indexes advanced, while the rest sagged, led by a decline in rate-sensitive utilities, down 2.8 percent.
The selloff in stocks that began last week has been built on concerns over higher interest rates and lofty valuations.
Some strategists view it as a healthy pullback after a rapid run-up in the start of the year and strong 2017 gains, and say the improving economic outlook is a positive for stocks overall.
The Dow Jones Industrial Average fell 68.41 points, or 0.28 percent, to 24,277.34, the S&P 500 lost 15.02 points, or 0.57 percent, to 2,633.92 and the Nasdaq Composite dropped 3.89 points, or 0.06 percent, to 6,963.64.
The pan-European FTSEurofirst 300 index lost 2.50 percent and MSCI's gauge of stocks across the globe shed 1.55 percent.
Emerging market stocks lost 2.62 percent
Earlier, Taiwan's main index lost 5.0 percent, its biggest slump since 2011, Hong Kong's Hang Seng Index dropped 5.1 percent and Japan's Nikkei dived 4.7 percent, its worst fall since November 2016, to four-month lows.
U.S. Treasury prices gained as volatile equity markets led investors to seek out lower-risk bonds, though many investors remained nervous after a week-long bond rout sent yields on Monday to four-year highs.
Benchmark 10-year notes last rose 12/32 in price to yield 2.7507 percent, from 2.794 percent late on Monday.
The original trigger for the equities sell-off was a sharp rise in U.S. bond yields late last week after data showed U.S. wages increasing at the fastest pace since 2009. That raised the alarm about higher inflation and, with it, potentially higher interest rates.
"Once rates started moving, that kind of exposed some of these levered short VIX sales. A very crowded trade, it just took a while to unwind that," said John Lynch, Chief Investment Strategist at LPL Financial in Charlotte, North Carolina.
Commodities remained gloomy, with oil and industrial metals all falling as the year's stellar start for risk assets rapidly soured.
U.S. crude fell 1.25 percent to $63.35 per barrel and Brent was last at $66.83, down 1.17 percent.
Copper lost 1.20 percent to $7,083.00 a tonne.
The dollar rose to its highest in more than a week against a basket of currencies as traders piled back into the greenback amid the rout in stocks.
The dollar index last was flat, with the euro up 0.21 percent to $1.2393.
(Additional reporting by Chuck Mikolajczak and Sinead Carew in New York, Marc Jones and Helen Reid in London and Hideyuki Sano in Tokyo; Editing by Bernadette Baum and James Dalgleish)