Background: For the past 30 years, the neoclassical finance has been questioned bybehavioural finance. The main difference is behavioural finance ́s ability to explain a behaviour that deviate from rationality. One of the major biases within behavioural finance is overconfidence. Overconfident behaviour describes an investor with too strong belief in their own ability. This bias is not well-examined within behavioural finance in Sweden. The consequences of overconfidence are the investor ́s overvaluation skills which in turn leads to unnecessary risk-taking, excessive trading and economic losses. Purpose: The purpose of this thesis is to investigate if the overconfident bias exists among Swedish private investors. A study if the demographic factors; gender, age, marital status, education, and experience effect the level of overconfident behaviour. Further, an investigation to identify industries overconfident investors prefer or despise. Method: Our study use a deductive approach with a quantitative research. From the basis of previous studies, five hypotheses explaining a relation between demographic factors and overconfidence have been formulated. The data is collected through an online survey, published in finance forums between 2020-03-10 to 2020-03-22 which gave 233 participants. A binary logistic model was performed in STATA to examine if the hypothesis should be rejected or not. Conclusion: The findings from our study show presence of overconfidence among Swedish private investors. Statistically significant results confirm that gender, age, education, and experience have an impact on overconfident behaviour. Men are more overconfident than women, younger investors act more overconfident, higher education increase overconfidence, and more experienced investors are more overconfident.

We find that the first investment of a private investor in an IPO affects the private investors future participation in IPO’s. This paper examines Nasdaq Stockholms Main list during 2010-2019. The short- and long-term perspective is examined by two different models. The results show that there is a significant difference between private investors when it comes to participating in future IPO’s, depending on if the private investor experienced a good or bad IPO. The result in this paper show that approximately a third more private investors participate in the upcoming IPO after they experienced a good IPO. In a longer perspective approximately 50% of the investors who experienced a good IPO choose to invest in at least one more IPO.  Out of the private investors who experienced a bad IPO, approximately 30% choose to participate in another IPO. This paper contribute to a better understanding of how private investors are affected by their earlier investments.

This thesis presents an attempt to find evidence of the ostrich effect and the disposition effect, as well as individual differences in self-assessed financial knowledge and its effect on these biases. The ostrich effect refers to the tendency to deliberately avoid information that might be negative, by "sticking your head in the sand". The disposition effect refers to people who hold on to losing assets too long while selling winning ones too early. The two effects were examined through a natural experiment which emerged from the stock market crash that occurred February 5th, 2018. The data was collected during an internship at Länsförsäkringar AB and originates from the usage of Länsförsäkringar's application Sparnavigatorn, where customers can manage their savings. The customers login activity and number of placed sales orders were observed. The data material is unique, and the study enabled a unique presentation of real life behaviour within a financial context and an analysis of whether individual differences affect behaviour. To our knowledge, neither the ostrich effect nor the disposition effect have earlier been examined through a large scale natural experiment. The results show no significant indication of the ostrich effect, but rather a relatively constant login activity not affected by the stock market crash. Furthermore, they show a contradictory reaction to what the disposition effect suggests, meaning the respondents place more sales orders during the stock market fall than at the time before and after. The results imply that further research needs to be done to either reject or confirm the existence of the ostrich effect and the disposition effect.