Nielsen Holdings' (NISN.US) stock price is influenced by a variety of factors. Company Performance: Nielsen's financial results, including revenue, profit margins, and earnings per share, directly impact investor confidence and stock value.

Industry Trends: The overall health and growth prospects of the media measurement and data analytics industries play a crucial role in determining Nielsen's valuation.

Competition: Competitive pressures from rival companies offering similar services can affect Nielsen's market share and pricing power, influencing its stock price.

Economic Conditions: Broader economic factors such as GDP growth, inflation rates, and interest rates can impact consumer spending and advertising budgets, affecting Nielsen's business.

Regulatory Environment: Changes in regulations related to data privacy, media ownership, or advertising standards can impact Nielsen's operations and profitability.

Mergers and Acquisitions: Potential or actual mergers, acquisitions, or divestitures involving Nielsen can significantly impact its stock price due to changes in the company's structure and strategy.

Investor Sentiment: Overall market sentiment and investor risk appetite can influence the demand for Nielsen's stock, leading to price fluctuations.

Technological Advancements: Disruptive technologies or new measurement methodologies can impact Nielsen's ability to stay competitive and maintain its market leadership.

Management Decisions: Strategic decisions made by Nielsen's management team, such as investments in new technologies or expansion into new markets, can influence investor perceptions of the company's future prospects.