If a judge is in a good mood because something nice happened to her daughter, or because a favorite sports team won yesterday, or because it is a beautiful day, her judgment might be more lenient than it would otherwise be. This within-person variability is conceptually distinct from the stable between-person differences that we have just discussed—but it is difficult to tell these sources of variability apart. Our name for the variability that is due to transient effects is occasion noise.
