Feeling the Same, Seeing the Same: Actual and Perceived Affect Similarity in Romantic Relationships

For a full detailed description of the study context, hypotheses, data, methodology used, and model specifications, see attached document (using OSF template) 'OSF Preregistration_Feeling The Same_Seeing The Same_Geert Van Dingenen.pdf. This description gives a brief and summarised overview. This preregistered research investigates the association between affect similarity and relationship quality in romantic couples. We move beyond simple difference scores by operationalizing similarity as "shared, co-experienced elevated affect". This metric combines dyadic elevation (mean level) with a penalty for mismatch (absolute distance), treating similarity as the extent to which partners are "up together" or "down together" relative to their baselines. We distinguish between Positive Affect (PA) and Negative Affect (NA) similarity, and disentangle actual similarity (objective alignment) from perceived similarity (subjective perception). Summary of key Hypotheses: 1. Main Effects: Higher actual PA similarity will predict higher relationship quality, whereas higher actual NA similarity will generally predict lower relationship quality. 2. Mediation: The link between actual similarity and relationship outcomes is mediated by perceived similarity. 3. Moderation: The impact of similarity depends on the relational context. We expect responsiveness and "we-ness" to amplify the benefits of PA similarity and attenuate the downsides of NA similarity. The impact of similarity also depends on event or interaction valence (i.e., is different in positive vs. negative contexts). The hypotheses are tested using data from the RE-Connect Consortium across two complementary components. Study component 1 uses Experience Sampling Methodology data to test how momentary affect similarity relates to momentary feelings of love in daily life and study component 2 uses laboratory interaction data to test how average affect similarity during the interaction relates to post-interaction love and closeness.