Dispositional attribution is the explanation of individual behavior as a result caused by internal characteristics that reside within the individual, as opposed to external (situational) influences that stem from the environment or culture in which that individual is found. Dispositionalism is the general tendency to prefer dispositional attribution rather than situational attribution.
Another term for dispositional attribution is internal attribution. Internal attribution refers to inferring that personal factors are the cause of an event or behavior. Attributions refer to influences that you make regarding what caused an event or behavior and they are your attempt at understanding your experiences, behaviors, and the behaviors of others. When we use internal attributions, we infer that a person is behaving in a certain way or that an event is due to factors related to the person. Internal attribution is defined as the act of placing blame on some type of factor or criteria that could be controlled by an individual for the cause of a certain event. When making an internal attribution, we infer that an event or a person's behavior directly correlates to personal factors such as traits, abilities, or feelings. A simplified example of this can be shown when a woman is paying for her groceries at the cash register. When a cashier is short with her at the grocery store, the woman decides he must be a rude and crabby person all the time. Internal attribution is how we attach meaning to other's behaviors and even our own.
For example, dispositional optimism is a tendency that applies generally across situations, but situational optimism is having hope and expecting a good outcome in a specific situation.