Self-efficacy is mainly determined by the following sources of information: personal experience, observation, persuasion and emotion. When predicting their ability to succeed in a new task, individuals tend to review their past experiences in accomplishing similar tasks. This information usually has a strong impact on our sense of self-efficacy, which is logical: if you have done many things, you probably believe you can do it again. Personal experience also explains why it may be difficult to improve self-efficacy. When a person’s self-efficacy level for a task is very low, they usually avoid the task, which hinders them from accumulating positive experience that may eventually lead to self-confidence. When a person tries a new task and succeeds, the experience builds their confidence and produces a higher level of self-efficacy related to similar tasks. We also judge our abilities by observing others. Imagine that you have a friend who is famous for coaching potatoes, and then that friend runs a marathon successfully. This observation may convince you that you can also become a runner. Researchers have found that when we see others succeed in an activity through hard work rather than through innate ability, we are more likely to improve our self-efficacy in an activity. For example, if you have a low sense of self-efficacy in public speaking, observing a timid person develop this skill may help boost your self-confidence. Watching a naturally attractive, extroverted person make a speech is unlikely to produce the same effect. Observing others is more likely to affect our own self-efficacy when we feel that we are very similar to the person we are observing. In general, however, observing others does not affect our sense of self-efficacy as much as our personal experience does. Sometimes others may try to improve our self-efficacy by providing support and encouragement. However, this type of persuasion does not always have a strong impact on self-efficacy, especially when compared with the impact of personal experience. Bandura believes that emotions such as fear and anxiety can undermine our sense of self-efficacy. For example, you can have a high sense of self-efficacy in chatting and socializing, but if you are really nervous about making a good impression on a particular event, your sense of self-efficacy may decrease. On the other hand, positive emotions can produce a greater sense of self-efficacy. Psychologist Julian Rotter believes that self-efficacy is closely related to the concept of locus of control. Control points refer to how individuals determine the cause of events. People with internal control sources believe that events are caused by their own actions. People with external sources of control believe that events are caused by external forces (e.g., other people or accidental circumstances). After successful completion of a task, individuals with internal control sources experience greater self-efficacy than individuals with external control sources. In other words, bragging about your successes (rather than claiming that they happen because of factors beyond your control) is more likely to boost your confidence in future tasks. Bandura’s self-efficacy theory has many applications, including the treatment of phobia, the improvement of academic achievements, and the development of healthy behavior.