NEW YORK (TheStreet) -- RATINGS CHANGES

Alcoa (AA - Get Report) was upgraded at Deutsche Bank to buy from hold. Third-quarter results were better than expected, and turnaround is apparent in the upstream Primary smelting business due to improved global aluminum prices, Deutsche Bank said. Twelve-month price target was raised to $20 from $16.

Amazon.com (AMZN) was downgraded to sell at TheStreet Ratings. You can view the full analysis from the report here: AMZN Ratings Report.

Diamond Offshore (DO - Get Report) was downgraded at Goldman Sachs to sell from neutral. Fundamentals for offshore drillers continue to worsen, with more rigs idled and dayrates dropping as new rigs enter supply, Goldman said. Lower crude prices would further delay any potential demand recovery, the bank's analysts also said. Twelve-month price target was lowered to $26.50 from $36 due to lower estimates and lower target multiple, Goldman added.

Diana Shipping (DSX - Get Report) was downgraded at Deutsche Bank to hold from buy. Recent trip to China suggests reduced growth assumptions, Deutsche said. Twelve-month price target was lowered to $10 from $18.

Emerge Energy Services (EMES) was downgraded at Goldman Sachs to neutral from buy. Sand demand will be negatively impacted in a low commodity price environment, Goldman said. Twelve-month price target was lowered to $97 from $153.

Halliburton (HAL - Get Report) was downgraded at Goldman Sachs to buy from Conviction List Buy. With high exposure to U.S. land and pressure pumping, company should see reduced revenue along with group, Goldman said. However, increases in Mideast and improved profitability in Latin America support stock, Goldman also said. Twelve-month price target was lowered to $65 from $87. Valuation still remains attractive, Goldman concluded.

IHS (IHS) was downgraded at Barclays to equal weight from overweight. Valuation currently prices in growth at high range of estimates, leaving limited upside, Barclays said. Twelve-month price target was reduced to $135 from $150, Barclays said.

Oceaneering International (OII) was upgraded at Goldman Sachs to Conviction List Buy, said Goldman. Stock is expected to outperform in a slow growth environment, Goldman said.

Overstock.com (OSTK) was upgraded to buy at TheStreet Ratings. You can view the full analysis from the report here: OSTK Ratings Report.

Patterson-UTI Energy (PTEN) was downgraded at Goldman Sachs to neutral from Conviction List Buy. With WTI crude oil projected to average $74 in 2015, customer capital spending should see cuts leading to a sharp fall in rig count. As such, companies with U.S. land leverage face reduced outlook, Goldman said. Twelve-month price target was lowered to $26 from $43.

Vivint Solar (VSLR - Get Report) was initiated at Deutsche Bank with a buy rating. Company is one of the top residential solar installers in the country and is poised to benefit from the accelerating growth of retail customers switching to solar, Deutsche Bank said. Twelve-month price target is $20.

Wayfair (W) was initiated at Pacific Crest with an outperform rating. Leading home goods retailer is growing roughly twice as fast as the industry, Pacific Crest said. Initial price target was set at $39.

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This article was written by a staff member of TheStreet.