The document discusses using machine learning algorithms and text mining of financial news headlines to predict stock market changes. It tests various algorithms, including Bayesian classifiers and support vector machines, on headline data from seven companies. The Bayesian classifier achieved the best results but prediction accuracy remained below 50%. While sophisticated models may eventually outperform by better understanding language, current methods cannot easily match human-level analysis of headlines. With continued improvement in algorithms and data mining, prediction accuracy may increase in the future.