We propose a dyadic Item Response Theory (dIRT) model for measuring interactions of pairs of individuals when the responses to items represent the actions (or behaviors, perceptions, etc.) of each individual (actor) made within the context of a dyad formed with another individual (partner). Examples of its use include the assessment of…

Reversing characters (digits and letters) when writing, and complete mirror writing, raise one of the oldest and most mysterious questions in developmental and educational psychology: Why do five-year-old children write symbols (e.g., [reversed E] for E) they have neither learnt nor seen? Attempts to draw up a complete explanatory theory of…