The impossibility of separating age, period and cohort effects

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Bell, A.J. ; Jones, K. (2013)
  • Publisher: Elsevier

This commentary discusses the age–period–cohort identification problem. It shows that, despite a plethora of proposed solutions in the literature, no model is able to solve the identification problem because the identification problem is inherent to the real-world processes being modelled. As such, we cast doubt on the conclusions of a number of papers, including one presented here (Page, Milner, Morrell, & Taylor, 2013). We conclude with some recommendations for those wanting to model age, period and cohort in a compelling way.
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