Goldman Sachs has reiterated its 'sell' recommendation on publisher Pearson, saying that the stock's valuation is "full" while the business faces many challenges.It said that issues over lower estimated structural growth and increased competition are not being reflected in the stock, which is now trading at 14.9 times earnings estimates for 2015.Numis Securities has maintained a neutral stance on shares of Carnival but said that the investment case is "starting to look more interesting".The broker said that it is in "no rush to buy" but the potential for a recovery in yields and growth at the cruise operator "remains enticing". It pointed out that for every 100 basis-point increase in yields leads to a rise in earnings of around 8%.In spite of a cautious outlook from home furnishings retailer Carpetright this week, analysts at Deutsche Bank have upgraded their rating on the stock from 'sell' to 'hold' after a recent sell-off."Our [target price] falls to 510p [from 545p] but following recent share price weakness and ahead of new Chief Executive Officer Wilf Walsh's imminent arrival we upgrade our recommendation to 'hold'."Westhouse Securities said that it was pleased with Wednesday's appointment of Finance Director Tony Durant to the position of Chief Executive Officer (CEO) at Premier Oil."Tony is well respected by investors and we think his appointment will affirm Premier's commitment to the key projects in the portfolio, particularly the Sea Lion development in the Falklands."Shares in newly-listed Card Factory received a boost on Wednesday after UBS initiated coverage of the stock with a 'buy' rating, hailing the company's "unique business model" and strong growth prospects.Card Factory designs, manufactures and sells its own greeting cards and this so-called 'vertical integration' provides protection for industry-leading margins and gives the company a "sustainable competitive advantage", UBS said in a research report.BC