Imaginal Process Inventory

The Imaginal Process Inventory (IPI) was a daydream questionnaire developed n the late 1960s, by psychologists Jerome L. Singer of Yale University and psychologist John S. Antrobus of the City College of New York.

It has been used to investigate daydreams. Psychologists Leonard Giambra and George Huba used the IPI and found that daydreamers' imaginary images vary in three ways: how vivid or enjoyable the daydreams are, how many guilt- or fear-filled daydreams they have, and how "deeply" into the daydream people go.