Question 3: Information effectiveness in stock markets is one of the widely debated topics in financial management theory and has been the subject of numerous scientific studies in recent decades. There is a combination of popularity, controversy, and criticism that may indicate that an idea of ​​interaction between information and stock prices has multiple values. What does an efficient market mean? In an absolutely efficient market, the current value of the security share is always equal to the investment value (a fair price), which is assessed by a large number of well-informed and highly professional market analysts. There are certain terms for a “perfect market”. A large number of investors - sellers and buyers, therefore, a single transaction does not influence the entire market. All information is fully and freely accessible to everyone. The absence of associated costs such as payment for transactions, taxes or market membership fees. The expectations of all market participants regarding economic indices and presumed outcomes are the same. There is however a note to the above, not all of these conditions can be fully implemented in a real market: the information is not free, taxes and overheads exist, investors can have an account different (e.g. short or long). terms strategies). The basic theory describing market information efficiency is the efficient markets hypothesis (EMH). Information is efficiently classified based on how quickly and accurately security prices react to new information, so that no one can earn an abnormal return. All information can be divided into three types: past information, publicly available information, and all information. In accordance with the c......middle of paper......efficiency of Fama stock markets. In particular, G. Soros suggests that recent developments in stock markets have shown the insufficiency of the EMH. In addition, Warren Buffet, who made his fortune in the crisis of the 1970s, had the same point of view very early on, arguing that the market is not efficient. These opinions deserve attention, at least the authors achieved a practical result – they made money. In conclusion, a stock market is a very complicated “machine” that includes an infinite mix of constantly changing factors. It would be futile to draw unambiguous conclusions about the effectiveness of information when there are too many controversial and compelling arguments. However, despite the evidence supporting efficiency, the anomalies detected could be considered contradictory to the EMH and these anomalous effects could undermine the efficient market theory..