Cohu (COHU) could be a solid choice for investors given the company's remarkably improving earnings outlook. While the stock has been a strong performer lately, this trend might continue since analysts are still raising their earnings estimates for the company.The upward trend in estimate revisions for this maker of semiconductor test equipment reflects growing optimism of analysts on its earnings prospects, which should get reflected in its stock price. After all, empirical research shows a strong correlation between trends in earnings estimate revisions and near-term stock price movements. This insight is at the core of our stock rating tool -- the Zacks Rank.The five-grade Zacks Rank system, which ranges from a Zacks Rank #1 (Strong Buy) to a Zacks Rank #5 (Strong Sell), has an impressive externally-audited track record of outperformance, with Zacks #1 Ranked stocks generating an average annual return of +25% since 2008.Consensus earnings estimates for the next quarter and full year have moved considerably higher for Cohu, as there has been strong agreement among the covering analysts in raising estimates.The chart below shows the evolution of forward 12-month Zacks Consensus EPS estimate:12 Month EPSCurrent-Quarter Estimate RevisionsThe earnings estimate of $0.50 per share for the current quarter represents a change of +5100% from the number reported a year ago.Over the last 30 days, three estimates have moved higher for Cohu compared to no negative revisions. As a result, the Zacks Consensus Estimate has increased 337.5%.Current-Year Estimate RevisionsThe company is expected to earn $0.95 per share for the full year, which represents a change of +955.56% from the prior-year number.In terms of estimate revisions, the trend for the current year also appears quite encouraging for Cohu. Over the past month, four estimates have moved higher compared to no negative revisions, helping the consensus estimate increase 144.74%.Favorable Zacks RankThanks to promising estimate revisions, Cohu currently carries a Zacks Rank #2 (Buy). The Zacks Rank is a tried-and-tested rating tool that helps investors effectively harness the power of earnings estimate revisions and make the right investment decision. You can see the complete list of today's Zacks #1 Rank (Strong Buy) stocks here.Our research shows that stocks with Zacks Rank #1 (Strong Buy) and 2 (Buy) significantly outperform the S&P 500.Bottom LineWhile strong estimate revisions for Cohu have attracted decent investments and pushed the stock 25.2% higher over the past four weeks, further upside may still be left in the stock. So, you may consider adding it to your portfolio right away.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Cohu, Inc. (COHU): Free Stock Analysis Report To read this article on Zacks.com click here.