* 200-day moving average has become support for Nikkei-analyst Japanese market valuations attractive - analysts
* But mixed data from U.S. leaves market worried
* Mazda soars on outlook hike
TOKYO, Feb 6 (Reuters) - Japan's Nikkei average edged higher on Thursday morning as investors bought shares of companies with strong earnings prospects, but gains were limited as the market stayed cautious ahead of the U.S. nonfarm payrolls report due on Friday. The Nikkei was up 0.4 percent at 14,230.69 in midmorning trade, still hovering near a four-month low of 13,995.86 hit the previous day. The benchmark was still trading below its 200-day moving average, which had been seen as a long-term support line. "The 200-day moving average (of 14,431.87) has become a resistance level," said Takuya Takahashi, a strategist at Daiwa Securities. "We are seeing a technical rebound, but people are very, very cautious." The Nikkei has dropped 4.8 percent so far this month and is down 13 percent in 2014. But analysts said the Japanese market offered attractive valuations, with the Nikkei trading at 13.7 times expected earnings, while the S&P is trading at 16.82 times, according to Thomson Reuters Starmine. "Japanese corporate fundamentals are strong at the moment," Hiromichi Tamura, chief strategist at Nomura Securities, wrote in a report. On Thursday, Mazda Motor Corp soared 7.1 percent to a one-week high after the carmaker raised its annual operating profit forecast by 12.5 percent to 180 billion yen ($1.8 billion). Bellwether exporters were mixed as investors stayed cautious despite an easing of worries about the yen's recent rise. The dollar stood at 101.46 yen, still within sight of a low of 100.755 yen touched on Tuesday. A strong yen cuts exporters' competitiveness abroad as well as their overseas profits. Toyota Motor Corp and Honda Motor Co both fell 0.7 percent, while Sony Corp was flat. The Topix shed 0.1 percent to 1,162.02. U.S. data painted a mixed picture on growth. The Institute for Supply Management said growth picked up in the dominant U.S. service sector in January, with steady strength in private-sector hiring, while the ADP National Employment Report showed U.S. private employers added 175,000 jobs in January, just shy of analysts' expectations. Investors remained cautious with the U.S. nonfarm payrolls report looming on Friday as last month's surprisingly low jobs number was discounted by many as an outlier negatively affected The JPX-Nikkei Index 400, an index launched this year comprised of firms with high return on equity and strong corporate governance, dropped 0.2 percent to 10,505.09.