THE MOMENTUM EFFECT EXEMPLIFIES THE INFLUENCE OF INVESTORS’ IRRATIONAL BEHAVIOUR ON CHANGING PRICES OF SHARES AND STOCKS: AN ANALYSIS OF THE MOMENTUM EFFECT ON THE WARSAW STOCK EXCHANGE

Abstract

An efficient market should not show any anomalies. When new information reaches a market which is efficient, it should automatically translate into prices of assets, which ought to eliminate the possibility of gaining an advantage over other investors, thus preventing excess profits. However, studies on capital markets indicate that in reality it is possible to earn unusually high profits by taking advantage of certain anomalies which occur on a given market. Among such anomalies there is the momentum effect. This study performed on the Stock Exchange in Warsaw has shown that the momentum effect occurred throughout the entire analyzed time period. Positive returns demonstrated for investment strategies based on the momentum effect were unexplainable by the classical theory of finances. A correlation was found between the economic situation on the stock exchange and portfolio return rates, but it was too weak to attribute the effect to a single decisive factor. In addition, the returns from investments based on the momentum effect were statistically higher in January than in the other months, which was caused by the January effect, stimulating the occurrence of statistically higher returns at the beginning of a year rather than later on during the analyzed period of time.