BMI
What's the goal?
A numerical goal lends direction to a design problem; a ratio works to make the subjective less so.
One of the best, worst and therefore most controversial metrics is Body Mass Index (BMI). Its utility stems from being simple to calculate: weight divided by square of height in metric units. BMI's inelegance drives detractors nuts.
The most relevant criticism is that it's nonsensical. BMI uses metric units, yet the ratio remains popular only in the USA (last to metricate, along with Liberia and Myanmar) to track the obesity epidemic. Calculated as mass over crude approximation of surface area, BMI corrupts the square-cube law it's meant to mimic.
What BMI does well is abstract away from normative (good / bad) toward health (healthy / unhealthy). We could all pick our favorite image above, but that's got nothing to do with health. Measuring body fat percentage or conducting active fitness tests would surely prove more insightful. But in terms of guiding folks through law of averages towards relevant self-steering, BMI is okay.
It would be great if every goal had a single metric (e.g., 1.5 to stay alive). But if simplified to that level, folks argue. So create an index and stop the debate - abstract until palatable for everyone to problem solve from neutral footing.
We have two favorites for this discussion:
(1) normalizing economic growth by carbon intensity
(2) striving for equity in transportation access, the most transformative global good on offer
Our rough draft for (1) would be (GDP growth per capita PPP) / (percentage change in carbon emissions from 2005 baseline). Negative numbers are good in the denominator while maintaining growth up top, but exceedingly rare. A double negative (i.e., numerator too) could be the best outcome while we get on a more sustainable pathway. What the USA did last year should not be repeated. Sadly, China has been improving carbon intensity three years earlier than 2020 goal, but overall emissions rose. Economic stagflation on top of increased carbon intensity usually occurs in failed states, highlighting the power of this metric. If the metric on the bottom were carbon intensity, developing countries would have more opportunity to grow unfettered. Sadly, we do not have time as a species to delude ourselves with such thinking.
Unexpectedly, the best holistically sustainable input to improvement that we never considered until recently might be to chase Universal Basic Mobility (UBM) while electrifying transportation and decarbonizing electric power generation.
What's your metric, ratio or index to pull us out of debate and into action?
A numerical goal lends direction to a design problem; a ratio works to make the subjective less so.
One of the best, worst and therefore most controversial metrics is Body Mass Index (BMI). Its utility stems from being simple to calculate: weight divided by square of height in metric units. BMI's inelegance drives detractors nuts.
The most relevant criticism is that it's nonsensical. BMI uses metric units, yet the ratio remains popular only in the USA (last to metricate, along with Liberia and Myanmar) to track the obesity epidemic. Calculated as mass over crude approximation of surface area, BMI corrupts the square-cube law it's meant to mimic.
What BMI does well is abstract away from normative (good / bad) toward health (healthy / unhealthy). We could all pick our favorite image above, but that's got nothing to do with health. Measuring body fat percentage or conducting active fitness tests would surely prove more insightful. But in terms of guiding folks through law of averages towards relevant self-steering, BMI is okay.
It would be great if every goal had a single metric (e.g., 1.5 to stay alive). But if simplified to that level, folks argue. So create an index and stop the debate - abstract until palatable for everyone to problem solve from neutral footing.
We have two favorites for this discussion:
(1) normalizing economic growth by carbon intensity
(2) striving for equity in transportation access, the most transformative global good on offer
Our rough draft for (1) would be (GDP growth per capita PPP) / (percentage change in carbon emissions from 2005 baseline). Negative numbers are good in the denominator while maintaining growth up top, but exceedingly rare. A double negative (i.e., numerator too) could be the best outcome while we get on a more sustainable pathway. What the USA did last year should not be repeated. Sadly, China has been improving carbon intensity three years earlier than 2020 goal, but overall emissions rose. Economic stagflation on top of increased carbon intensity usually occurs in failed states, highlighting the power of this metric. If the metric on the bottom were carbon intensity, developing countries would have more opportunity to grow unfettered. Sadly, we do not have time as a species to delude ourselves with such thinking.
Unexpectedly, the best holistically sustainable input to improvement that we never considered until recently might be to chase Universal Basic Mobility (UBM) while electrifying transportation and decarbonizing electric power generation.
What's your metric, ratio or index to pull us out of debate and into action?
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