Merger and acquisition activity looks set to rise in 2011, according to a new survey by Knowledge at Wharton and KPMG LLP. Nearly two-thirds of respondents to the survey were more optimistic about the merger and acquisition (M&A) environment this year compared with their attitudes a year earlier. Key reasons for the higher optimism include a more stable economic environment, stronger buyer confidence and improved debt and equity markets.The survey, conducted by Knowledge at Wharton in collaboration with KPMG LLP, generated 992 responses from executives at public companies, private firms, and hedge and private equity funds. Over half of the respondents were active buyers last year.