Abstract
The current SDG environment has enabled good progress in generating indicators across varying wellbeing dimensions as well as disaggregation. Most of the indicators are of a headcount construct and guided by a likelihood principle that poses difficulty in their comparison, valuation, and interpretation. Further, many of these indicators are sample estimates obtained through periodic surveys, which have their complexity in temporal and cross-sectional comparison, given their reliability conditioned by the frequency of the event. On this premise, I ask a question `Are we comparing the incomparable?’. In a headcount construct, comparability of a phenomenon needs a compositional/characteristic equivalence of the denominator, and we see them often overlooked. This is otherwise termed as standardisation. Besides standardisation, in case there is a characteristic risk association of the denominator population with the phenomenon in the numerator, head count measures and their comparison can be misleading. Head count measures and its guiding principle of likelihood make it qualified for comparison, but with a contradiction with the whole numbers that calls for consideration of fractions and whole numbers together. When indicators are sample estimates with their reliability depending on the width of the confidence interval, it poses another difficulty in comparative reading of the more reliable, along with the less reliable. There are indicators formulated in terms of qualification/disqualification of a benchmark, like deprivation, poverty, nourishment, etc. wherein the distribution on either side of the benchmark is ignored while comparing changes in the indicator. This makes one apprehensive of the distribution blind comparison. Another limitation of measures with a head count construct could be the mere addition paradox, wherein the denominator is added with numbers without any share in the numerator, and similarly, there can be addition in the numerator which is entirely anti-phenomenal, giving rise to a change that is not associated with the phenomenon. Finally, valuation and comparison being the fundamental motivation of conceptualising a measure, attention needs to be paid towards its robustness and the trade-off made between simplicity and adequacy.

Speaker Bio
Prof. Udaya Shankar Mishra is currently a Professor at the International Institute of Population Studies, Mumbai and a former Professor at the Centre for Development Studies, Kerala. He is engaged in research and teaching on population and development issues and has several national and international publications to his credit. In recent times, he has served in various capacities in guiding scientific research in the social sciences. During the two-and-a-half decades of his teaching and research experience, he has contributed research to the areas of ageing, health, and nutrition as well as population policy and programme evaluation. He holds a PhD from IIPS. He also served as a Temporary technical advisor for the World Health Organization for a while.