Demographic Distortions of Education Participation Measures

While seemingly straightforward, many common indicators of educational participation, such as enrolment ratios, are subject to distortions that are transparent from within a demographic framework, but generally ignored in the field of educational development. We propose to present on the full range of effects mentioned above at the conference, but as an example, here we elaborate in greater detail on the issue of the age composition effect.
The value of aggregate education indicators such as enrolment rates is influenced by the age structure of the population through a pure composition effect. This phenomenon is not generally acknowledged in educational statistics, much less accounted for. The scant treatment the question of age distribution has received in this context has been limited to examining it as a source of measurement error when comparing administrative and survey data sources. By using an age-standardization technique, we show how this very common demographic tool can straightforwardly be applied to educational metrics and how doing so alters the results. We conclude that the effect on net participation rates is moderate in general, but with respect to gross rates, parity indices and their changes over time, age standardization appreciably influences conclusions about educational system performance.