The stock exchange in Indonesia acts as a means of financial resources of business and investment for the community. Any investor needs some profit from his/her investment. However, in determining a policy for decision making, many investors do not always think, rationally. Moreover, stock trading in the stock exchange/money market faces with high uncertainty, which may create some ir-rational acts and leads to irrational investment decisions. This study aims to test the biased inves-tor’s behavior, such as overconfidence, disposition effect, and risk tolerance on investor’s trading activities in the Indonesian Stock Exchange. To analyze the qualitative response variable in this re-search, the researchers considered more than two categories. Therefore, the analysis required was Multi-nominal Logistic Regression Model. Meanwhile, some investors appointed to be the subject in this research were the customers of some Securities. The survey distributed 170 questionnaires and collected 141 properly filled ones used in this research. The testing result employing simultaneous multi-nominal logistic regression show that the overall model used was quite significant. The testing conducted partially also shows that only overconfident investors were affected by trading activities. Meanwhile, the opportunity of the overconfident investor to do trading was considered to be moderate as much as 0.177 multiplied from the “infrequent” category.

The current pandemic era has given uncertainty to the country's economic growth and resulted in many countries experiencing a drastic decline in share prices. This condition impacts investors' perceptions of the funds that have invested in the stock market. This study investigates the effect of essential information and disposition effect on shifting decision investment with the character investor's moderation as the moderator variable. A survey was conducted on 252 investors who have invested in the Indonesian stock exchange. The Data processing used the partial least square (PLS) technique. This study indicates that essential information for investors in the pandemic era can increase the disposition effect in deciding beneficial share ownership. The essential information obtained by investors in the covid era regarding stock market movements and its internal performance in the stock market list can increase investor shifting decisions. The disposition effect can have a significant effect on shifting decision investors. Essential information related to stock price movements and its internal performance affects investors' courage to take risks and provide optimism for shifting decisions. Then the investor type does not affect the disposition effect on shifting decisions. This study contributes to the theory of financial behavior in decision making by considering psychological factors when uncertainty exists in the stock market.