Social Judgment Theory proposes that people evaluate messages based on their existing attitudes or "anchor points" on issues. Messages are judged as falling within a latitude of acceptance, rejection, or non-commitment. The more ego-involved people are in an issue, the more strongly anchored and less open to persuasion their attitudes tend to be. For effective persuasion, messages need to fall just within the latitude of acceptance rather than rejection to avoid a "boomerang effect" and promote gradual attitude change over time.