How long do situations of single parenthood last? An estimation based on French data

[eng] Single-parent families currently account for over 20% of families with minor children in France, in line with the European average. Single parenthood is often associated with greater risks of insecurity and exclusion, to which social policies must respond. It is thus important to know how long such situations last. In this paper, we present an original method for estimating the duration of such periods based on a sample of single parents for whom only the length of time spent in the situation at the time of the survey is observed (stock sampling). It combines a calculation of the likelihood function of the observations using the methodology proposed by Nickell and the introduction of proportional instantaneous probability of exiting the situation based on the Cox model. Several simulations replicating a variety of observed scenarios confirm the reliability of this method. Applying this method to the data from the 2011 Family and Housing Survey allows us to estimate that single parenthood ends after 3 years for half of the single parents.