Assurant ( AIZ) upgraded at Keybanc from Hold to Buy. $65 price target. Company deserves a premium multiple to its peers, given its above-average 16.5% ROE. Estimates also raised, to reflect higher returns in the specialty property division. Apollo Group ( APOL) upgraded at Baird from Neutral to Outperform. $80 price target. Positive enrollment trends are helping to improve margins. The company's international joint venture should also help drive growth. Check Point Software ( CHKP) downgraded by Jefferies. Rating lowered to Neutral from Buy. 2007 EPS estimates raised $1.57 from $1.55. Price target lowered to $28 from $30. Diamond Offshore ( DO) upgraded at Morgan Stanley from underweight to overweight and moves price target to $145. Frontier Airlines ( FRNT) upgraded at JP Morgan from Underweight to Overweight. Competition is cutting back on capacity and the company's RASM should continue to accelerate. Estimates also raised. Gold Fields ( GFI) upgraded at Goldman Sachs to Buy from Neutral based on valuation and leverage to gold prices. Note that company offers highest leverage to today's bullish gold price upgrade. Believe risk profile has improved with divestiture of assets in Venezuela and Burkina Faso. Production start-up at Cerro Corona (Peru) provides another driver for 2008. Price target increased to $23 from $19. Hub Group ( HUBG) downgraded at Baird from Outperform to Neutral. $31 price target. Intermodal volume and overall pricing was disappointing in the third quarter. Estimates also cut, and the stock lacks near-term catalysts.