In the paper is considered identification of coefficients in equations explaining a continuous variable, say the number of sickness absence days of an individual per year, by cohort, time and age, subject to their definitional identity. Extensions of a linear equation to polynomials, including...

Identification of equations explaining a continuous variable, e.g., the length of sickness absence spells, by age, cohort and time (ACT), subject to their definitional identity is reconsidered. Various extensions of a linear equation to polynomials are explored. If no interactions between the...

When using data from individuals who are in the labour force to disentangle the empirical relevance of cohort, age and time effects for sickness absence, the inference may be biased, affected by sorting-out mechanisms. One reason is unobserved heterogeneity potentially affecting both health...

When using data from individuals who are in the labour force to disentangle the empirical relevance of cohort, age and time effects for sickness absence, the inference may be biased, affected by sorting-out mechanisms. One reason is unobserved heterogeneity potentially affecting both health...

We examine the remarkable rise in absenteeism among Norwegian employees since the early 1990's, with particular emphasis on disentangling the roles of cohort, age, and time. Based on a fixed effects model, we show that individual age-adjusted absence propensities have risen even more than...