Earnings season brings on a flurry of upgrades and downgrades, and it can be an all-day affair just to get through them all. Today we look at two international tech stocks, a produce provider, and a media conglomerate. Should you pay attention to Wall Street's call?

Company

Rating

Reaction as of 1 p.m. ET

Youku.com (NYSE: YOKU) Upgraded from Hold to Buy Up more than 1.5%
Dole Foods (NYSE: DOLE) Downgraded from Buy To Hold Down more than 3%
Discovery Communications (Nasdaq: DISCA) Downgraded from Outperform to Perform Near flat
Yandex (Nasdaq: YNDX) Upgraded from Underweight to Neutral Down almost 3%

Source: The Wall Street Journal.

Here's some more color on these analyst moves.

Youku.com
The Maxim Group upgraded Youku to Buy from hold.

  • Why? Maxim is anticipating a stronger earnings release next week, with potentially decreasing content costs and higher market share as the acquisition of Tudou is completed.
  • Justified? No. Youku happens to be one the better publicly traded Chinese companies available to U.S. investors, though I believe the acquisition of competitor Tudou was overpriced and premature for the quickly growing Internet video service. More time is needed to determine whether Tudou will materially benefit Youku's long-term strategy.

Dole Foods
Auriga downgraded Dole to Hold from Buy.

  • Why? Auriga downgraded the stock based on valuation, as it has run up since the company's earnings release earlier this month.
  • Justified? Mixed. Dole is not my industry pick, based on its forward earnings ratio compared with the expected growth. Chiquita Brands (NYSE: CQB) is expected to grow much more at a very attractive valuation. Dole management has recently been talking about a possible spinoff to help realize hidden value in the company, though, which has the potential to be lucrative for both Dole and its spun-off segment if the deal goes through.

Discovery Communications
Barrington Research downgraded Discovery from Outperform to Market Perform.

  • Why? Barrington likes the business and recognizes Discovery as an industry leader but is changing its rating based on new valuation.
  • Justified? No. This, like many analyst ratings, looks like a move to hedge the firm's previous call. Barrington was probably a little overzealous in its previous valuation of Discovery and is now correcting it. What it should be noting in its announcement is Discovery's stake in the Oprah Winfrey Network. OWN has struggled since inception, though both Discovery and OWN management are very confident in the long-term future of the network.

Yandex
HSBC Securities upgraded Yandex from Underweight to Neutral.

  • Why? HSBC upped its price target from $21.50 to $23.60, probably based on Yandex's recent earnings release, in which the Russian search engine missed analyst EPS estimates but still grew top line by more than 45%.
  • Justified? Yes. Yandex took a small hit after it missed EPS estimates, which isn't an unusual market overreaction in the short term. The company is the industry leader in Russia, and after an overpriced and overhyped IPO last year, the company is looking much more attractive at its current valuation.

Ratings are often based on short-term prospects and aren't relevant to the long-term investor. However, we can use them to dig up useful facts about a company we may not have seen before. It's important not to let the ratings themselves color your opinion of a company. As Fools often say, it's better to do the research yourself and come to your own conclusions. Keep an eye on this series to stay in the know.