Answer to Question 1
People generally attribute someone's behavior to internal and external causes. An internal attribution assigns the cause of behavior to some characteristic of the target and assigns credit or blame to the individual actor. Attributions to ability, effort, and personality are the most common internal attributions that people make.
However much people like to feel that they are in control of what happens in their lives, outside forces often play a decisive role in determining behavior. An external attribution assigns the cause of behavior to factors outside the individual. The most common external attributions relate to task difficulty and luck or chance.
The attributions people make for their own behavior influence their own subsequent actions. An employee who fails on a task and attributes this failure to a lack of ability may be likely to avoid the task in the future or exert minimal effort on it because he feels that his lack of ability will almost certainly guarantee a negative outcome. Conversely, attributing failure to a lack of effort may lead the employee to try harder in the future on the same task.
Answer to Question 2
The primacy effect is the initial information that a perceiver has about a target that has an excessive effect on the perception and evaluation of the target.
The contrast effect is the when the perceiver compares the target to those around the target. This can make the target stand out in either a positive or negative light.
The halo effect is the general perception a perceiver holds about a target, and which influences the perception of specific dimensions of the target.