M.I.C.E. stands for:

• Milieu: the setting
• Idea
• Character
• Event: the action

Good stories have multiple M.I.C.E. threads going on.

The formula for calculating the approximate length of a story (a rough predictor):

length = (#characters + #stages) * 750 * #threads / 1.5

Stage is scene or scenic location.

750 is the average of 500 and 1000.

See also: Video: Writing Science Fiction and Fantasy Lecture #7 (Brandon Sanderson, Mary Robinette Kowal)