On Universality in Human Correspondence Activity

TL;DR

This paper demonstrates that human correspondence patterns, including letters and emails, are governed by universal mechanisms such as circadian cycles, task repetition, and communication needs, across diverse individuals and communication modes.

Contribution

It shows that letter and email correspondence share underlying universal patterns, challenging the view that responses solely drive correspondence activity.

Findings

Letter and email patterns are governed by circadian cycles.

Universal mechanisms apply across different communication modes.

Rescaling correspondence data reveals underlying similarities.

Abstract

Identifying and modeling patterns of human activity has important ramifications in applications ranging from predicting disease spread to optimizing resource allocation. Because of its relevance and availability, written correspondence provides a powerful proxy for studying human activity. One school of thought is that human correspondence is driven by responses to received correspondence, a view that requires distinct response mechanism to explain e-mail and letter correspondence observations. Here, we demonstrate that, like e-mail correspondence, the letter correspondence patterns of 16 writers, performers, politicians, and scientists are well-described by the circadian cycle, task repetition and changing communication needs. We confirm the universality of these mechanisms by properly rescaling letter and e-mail correspondence statistics to reveal their underlying similarity.