Rates of return and the fundamental value of a company in the light of the assumption of investor’s rationality

Abstract

If investors were rational, they would buy the stock of companies which in their opinion represent the highest probability of generating profit or value growth. Therefore a positive correlation between a share price increase (as an indicator of investors’ confidence in the future prosperity of given company) and subsequent benefits should be evident. This, however, does
not always happen. One of the reasons why this seemingly natural relation is not observed may be that investors do not always behave rationally.  Another may be certain methodological issues discussed in the article. The research presented was based on a sample of 458 companies listed on the Warsaw Stock Exchange. The time period covered the years 1998-2015. It has been found that there is no linear dependency between quotations and the company’s end results understood as income per invested zloty and book value growth per invested zloty. The outcome of the research may have been disturbed by methodological factors, therefore in the research to
follow different risks, including differences in subgroups (sectors, small and big firms) as well as other ratios will be taken into account and the non-linear dependency will be verified.