Call Duration

Short calls were treated as less likely to represent meaningful emotional or social exchange. Longer-call and top-ranked-call analyses strengthened the interpretation because the same qualitative patterns persisted under restrictions to more emotionally meaningful contacts. Communication frequency and call duration were used as measurable proxies for social investment because emotional closeness is difficult to measure directly. The study repeated analyses across several duration thresholds because no single meaningful-call threshold could be chosen in advance. Duration remained an indirect proxy for emotional exchange even after multiple thresholds and ranked-call subsets were analyzed.