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Updated: Mar 2, 2026

Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
Published on: August 18, 2023
Abstract:
The recent rise in cohabitation in Britain is analysed using data from large-scale surveys. There are major inconsistencies between different sources, and retrospective estimates are higher than values reported at the time. Retrospective data show markedly smaller numbers of cohabitation events just before survey date. I discuss reasons for discrepancies and conclude that no objective measure of cohabitation exists and that comparison of different types of data requires care. I combine the data to produce a much larger data set than hitherto available. Although cohabitation prevalence increased substantially during the 1970s and 1980s, there was little change in such characteristics as duration of cohabitation, ages of those cohabiting, and whether it occurred before first marriage or ended in marriage or breakdown. However, since the late 1980s, the average length of cohabitation has increased markedly, which may indicate a qualitative change in the nature of cohabitation in Britain.
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